6′ x 12′ Kundel Basic 3 Steel Trench Box

The Kundel Basic 3 6′ x 12′ steel trench box is a durable utility shield designed for municipalities, plumbing contractors, industrial maintenance crews, and underground contractors using properly rated small excavators or rubber-tired backhoes.

This configuration combines a 6-foot sidewall height with a 12-foot overall length. Its extended working area makes it well suited to utility repairs, service connections, taps, minor mainline work, and maintenance excavations that require more longitudinal room than the shorter Basic 3 models provide.

The Basic 3 uses 3-inch double-wall, solid-welded steel sidewalls designed to provide dependable field performance without the weight associated with many larger conventional steel trench shields. The 6′ x 12′ model has a listed weight of approximately 1,960 lbs.

The 124-inch opening between spreaders provides substantial room for compatible pipe, valves, fittings, service connections, tools, equipment, and crew movement. Suitability depends on the actual dimensions and locations of the utility components and equipment used inside the shield.

This 6-foot-high box can be used independently where its dimensions and ratings are appropriate. It may also be used as an extension section on a compatible taller Basic 3 trench box when the complete stacked configuration is permitted by Kundel’s current tabulated data.

Each Basic 3 trench box requires four compatible spreaders. Spreaders are sold separately and must be selected according to the required inside width, excavation geometry, component clearances, lifting equipment, and manufacturer requirements.

Key Benefits & Crew Efficiency

• 6-Foot Sidewall Height: Provides useful vertical panel coverage for compatible utility repair and maintenance excavations.
• 12-Foot Overall Length: Provides the longest longitudinal work area among the 6-foot-high Basic 3 models in the Iron Lot catalog.
• 124 Inches Between Spreaders: Offers substantial open working space for compatible pipe, fittings, valves, tools, and service connections.
• Approximately 1,960 lbs: Designed for handling with properly rated compact excavators, small excavators, and rubber-tired backhoes.
• Steel Alternative to Aluminum: Provides durable welded-steel construction in a product line designed for smaller excavation equipment.
• Double-Wall Construction: Three-inch steel sidewalls are built for repeated use on demanding municipal, plumbing, and industrial maintenance projects.
• Solid-Welded Steel Design: Provides a durable structural assembly for regular field use.
• Cast Steel Spreader Collars: Durable collars provide attachment points for compatible Kundel Basic 3 spreaders.
• Forged Spreader Pins: Secure compatible spreaders within the box’s collar system.
• Integrated Tamping Blocks: Reinforced contact areas support manufacturer-approved positioning procedures.
• Integrated Lifting Lugs: Provide designated lifting points for properly rated rigging and equipment.
• Stackable Design: Compatible stacking rings may allow the box to be used as an extension section in an approved Basic 3 configuration.
• Tandem Capability: Approved tandem connectors may allow compatible boxes to be joined when an even longer working area is required.

Product Specifications

Pricing & Logistics

Price: $7,738.43

The listed price is for the Kundel Basic 3 6′ x 12′ trench box. Four compatible spreaders are required to assemble a complete box and are sold separately.

Contact Iron Lot to confirm current pricing, availability, compatible spreader lengths, stacking components, tandem connectors, optional accessories, applicable taxes, and freight charges.

Required Spreaders

Each Basic 3 trench box requires four compatible spreaders. The correct spreader length depends on the desired inside working width, excavation geometry, pipe or utility-component dimensions, and the limitations established in Kundel’s current tabulated data.

Spreaders should not be assumed to be included in the listed trench-box price. Confirm the required spreader size, quantity, forged spreader pins, and complete assembled configuration before ordering.

Optional Accessories

Available Basic 3 accessories may include:

• Compatible spreaders
• 12″ x 12″ utility cutout
• Stacking rings
• Tandem connectors
• Replacement forged spreader pins
• Compatible rigging and handling equipment

Optional accessories must be selected for the specific trench box and intended application. Confirm compatibility, pricing, and availability when requesting a quote.

Freight and Delivery Coordination

The trench box has a listed weight of approximately 1,960 lbs before adding spreaders, stacking rings, tandem connectors, rigging, or other accessories. The final assembled and shipping weight depends on the complete ordered configuration.

The 12-foot panel length requires suitable transportation, securement, unloading equipment, lifting capacity, and assembly space. The delivery and unloading plan should be confirmed before shipment.

Iron Lot can coordinate delivery to your contractor yard, municipal facility, equipment location, or jobsite.

Target Applications

The Kundel Basic 3 6′ x 12′ is designed for utility and maintenance excavations where crews need 6-foot vertical panel coverage and an extended longitudinal working area.

Typical applications may include:

• Water and sewer utility repairs
• Water-main and sewer-main taps
• Service-line connections
• Minor mainline work
• Valve, fitting, and curb-stop access
• Localized utility exposure and maintenance
• Gas-service connections
• Electrical and telecommunications work
• Plumbing repair excavations
• Industrial maintenance projects
• Emergency municipal utility repairs
• Work requiring additional room for components, tools, and crew movement

The 12-foot overall length provides more working room than the 6′ x 6′, 6′ x 7′, 6′ x 8′, and 6′ x 10′ Basic 3 models. This additional space may be useful for compatible pipe, valves, fittings, service connections, tools, rigging, and other equipment.

The longer box also requires more excavation and positioning space. Contractors should evaluate pavement limits, existing utilities, traffic-control restrictions, nearby structures, spoil placement, equipment access, and the available lifting radius before selecting this size.

Suitability depends on the actual dimensions and locations of the pipe, structure, fitting, valve, service connection, utility component, tools, and equipment used inside the shield. Customers should verify that the 124-inch length between spreaders and 27-inch pipe clearance provide adequate room for the intended work.

Standalone and Stacked Configurations

The Basic 3 6′ x 12′ may be used as a standalone trench box where its height, length, working clearances, depth ratings, and complete configuration are appropriate for the excavation.

As a 6-foot-high box, it may also be used as an extension section on a compatible taller Basic 3 base box. This type of stacked configuration can increase the total vertical panel coverage of the trench-protection system.

Stacked configurations must use the required Kundel stacking rings or other manufacturer-approved connecting components. The base box, extension section, selected spreaders, connection points, structural capacities, and complete stacked arrangement must be compatible and permitted by Kundel’s applicable tabulated data.

Do not stack trench boxes solely because their exterior dimensions appear compatible. Product line, panel length, spreader-collar arrangement, structural capacity, approved connection method, and the complete system configuration must all be verified.

Tandem Configurations

Compatible Basic 3 trench boxes may be connected in tandem to create a longer shielded work area when permitted by Kundel’s tabulated data.

Tandem configurations require approved connectors and a complete evaluation of the boxes, selected spreaders, connection locations, excavation geometry, utility dimensions, lifting plan, and manufacturer requirements.

The 12-foot box already provides an extended longitudinal working area. A tandem configuration should only be used when additional length is necessary and the complete connected arrangement is supported by the applicable manufacturer data.

Do not use improvised connections or assume that placing two trench boxes next to each other creates an approved tandem configuration.

Critical Selection & Safety Factors

Is the Kundel Basic 3 6′ x 12′ Right for Your Excavation?

The exterior height and length of a trench box do not by themselves determine whether it is suitable for a project.

The selection process should consider:

• Whether the box will be used independently, stacked, or in tandem
• Compatibility with any additional Basic 3 base box or extension section
• Excavation depth, width, length, and geometry
• Available longitudinal placement space
• Soil classification
• Surcharge loads
• Groundwater and changing soil conditions
• Traffic, structures, spoil piles, and equipment near the excavation
• Pipe, fitting, valve, structure, and utility-component dimensions
• Required longitudinal, vertical, and lateral working clearances
• Selected spreader length and resulting inside width
• Access and egress requirements
• Lifting, placement, and removal equipment
• Stacking rings, tandem connectors, and optional cutouts
• The complete protective-system configuration

The project’s Competent Person must inspect the excavation, classify the soil, evaluate changing conditions and adjacent hazards, and verify that the selected trench-protection system is appropriate for the excavation and used correctly.

Depth Ratings & Tabulated Data

The listed maximum soil depth ratings for the Basic 3 6′ x 12′ are:

• Type A soil: 31 feet
• Type B soil: 18 feet
• Type C soil: 14 feet

These ratings must be interpreted through Kundel’s current tabulated data. They do not mean that a 6-foot-high trench box automatically provides a shielded work area at the listed excavation depths.

The allowable depth may depend on whether the box is used independently or in a stacked configuration, the selected spreader width, complete system height, soil conditions, surcharge loads, excavation geometry, and other jobsite factors.

Placement of the trench box, including its position relative to the excavation bottom and the top of the excavation, must comply with Kundel’s instructions, current tabulated data, and applicable requirements.

Excavations exceeding 20 feet in depth generally require a protective system designed or approved under the applicable engineering requirements. Do not rely on product-page ratings as a substitute for Kundel’s current tabulated data or a project-specific engineered design when one is required.

Assembly, Lifting & Inspection

The Basic 3 trench box must be assembled with four compatible spreaders and the required forged spreader pins before use. Stacked or tandem configurations also require all approved connecting components.

The complete box should be lifted, lowered, repositioned, and removed using the designated lifting lugs, properly rated rigging, and equipment with sufficient capacity for the complete assembled weight.

The 12-foot panel length requires careful control during assembly, lifting, positioning, and removal. Tamping blocks provide reinforced contact areas, but all installation and positioning procedures must follow Kundel’s instructions.

Do not strike unapproved areas of the sidewalls, spreader collars, lifting lugs, or other structural components.

Before each use, inspect:

• Double-wall steel sidewalls
• Cast steel spreader collars
• Spreaders and forged spreader pins
• Tamping blocks
• Lifting lugs
• Stacking rings and connection points
• Tandem connectors
• Welds and structural areas
• Optional utility cutouts
• All components for cracks, bends, distortion, damage, or excessive wear

Damaged or questionable components should be removed from service until they have been evaluated according to the manufacturer’s requirements.

Why Choose the Kundel Basic 3 6′ x 12′?

The Basic 3 6′ x 12′ combines useful vertical panel coverage, an extended longitudinal working area, and durable welded-steel construction. It is designed for crews that need a longer steel trench shield that can be handled with appropriately rated smaller excavation equipment.

The 12-foot overall length provides more working room than the shorter 6-foot-high Basic 3 models. It may accommodate compatible utility components, valves, fittings, service connections, tools, equipment, and crew movement within a single shielded work area.

Projects with restricted longitudinal access or smaller utility components may be better suited to one of the shorter Basic 3 configurations. Selection should be based on the actual work rather than exterior box dimensions alone.

The double-wall steel sidewalls, cast steel spreader collars, forged pins, tamping blocks, and lifting lugs provide a durable field-ready system for municipal, plumbing, industrial maintenance, and underground utility crews.

Final selection must be based on the actual excavation, intended application, pipe or utility-component dimensions, selected spreaders, complete standalone or stacked configuration, Kundel’s current tabulated data, and the requirements established by the project’s Competent Person.

Request Pricing and Availability

Iron Lot supplies trench boxes and trench safety equipment to contractors throughout the United States.

Contact us for:

• Current product availability
• Spreader selection and pricing
• Multiple-unit quotations
• Freight quote and delivery coordination
• Alternative aluminum trench box options
• Steel versus aluminum trench box comparisons
• Equipment financing information

This Product Ships from Ohio

Payment Options:

We accept company check, wire transfer, ACH, and credit card payments. We also offer financing through Ascentium Capital.

Financing: Ascentium Capital offers fast and flexible financing. With their quick and convenient way to purchase equipment, working with Ascentium Capital helps you acquire the funds you need for your equipment purchase. With financing and leasing of up to $2,000,000, Ascentium Capital works with you to make the application process simple and at no obligation.

To learn more about Ascentium Capital and how it can assist you, click image below:

Call Iron Lot at 336-516-8011 or request a quote online for current pricing, availability, and freight information.

Not sure which trench box is right for your project? Compare additional trench boxes for sale, including steel, aluminum, and manhole box options.