Thomas & Betts 3211 One-Piece Knockout Bushing, 1.109" Plastic

Thomas & Betts 3211 One-Piece Knockout Bushing, 1.109" Plastic

The Thomas & Betts 3211 is a one-piece, non-metallic knockout bushing engineered to protect conductor insulation as wires and cables pass through knockout openings in electrical enclosures, panelboards, junction boxes, and cabinets. Molded from durable plastic in a single-piece design, this 1.109" bushing snaps securely into matching knockout openings without a separate locknut or additional hardware, providing a smooth, rounded internal edge that shields cable jacketing and wire insulation from abrasion, cutting, or chafing. Its non-metallic construction makes the 3211 a lightweight, corrosion-resistant, non-conductive alternative to traditional metal locknut-and-bushing assemblies, well suited for standard electrical wiring applications where a fast, hardware-free knockout closure is preferred. The 3211 is commonly specified as a direct-fit replacement for standard 1.109" knockout openings found in panelboards, meter enclosures, and junction boxes across residential, commercial, and industrial wiring projects.

Key Features

• Trade Size: 1.109" bushing diameter sized to fit matching knockout openings in enclosures, panelboards, and boxes.
• Durable Construction: Molded non-metallic plastic resists corrosion and will not conduct electricity, unlike traditional metal bushings.
• One-Piece Design: Single-piece molded body installs in one step with no separate locknut or hardware required.
• Knockout Protection: Smooth internal bore shields wire and cable insulation from sharp knockout edges during and after installation.
• Tool-Free Installation: Snaps into the knockout opening from inside the enclosure for a quick, secure fit without wrenches or additional fasteners.
• Non-Conductive Material: Plastic construction provides electrical insulation at the knockout opening, adding a layer of protection beyond bare metal edges.
• Lightweight Profile: Non-metallic plastic construction reduces overall enclosure weight compared to steel or malleable iron bushings.

Technical Specifications

• Refer to manufacturer documentation for complete technical specifications.

Typical Applications

• Electrical Panelboards and Enclosures
• Conduit and Raceway Knockout Openings
• Meter Enclosures and Junction Boxes
• Commercial and Industrial Electrical Installations
• Residential and Light Commercial Wiring
• New Construction and Renovation Wiring Projects

Why Thomas & Betts?

Thomas & Betts has long supplied electrical contractors and panel builders with dependable conduit and enclosure hardware, and the 3211 knockout bushing continues that tradition with a one-piece, non-metallic plastic body designed for straightforward installation and long-term durability. This hardware-free, single-piece design helps electricians protect wiring insulation, reduce installation time, and maintain clean, professional enclosure openings. Choose the Thomas & Betts 3211 when you need a dependable, corrosion-resistant, non-conductive bushing solution sized to fit 1.109" knockout openings in panelboards, boxes, and cabinets.