Thomas & Betts BLB-4 Conduit Bodies, Covers & Gaskets

The BLB-4 body is sold on its own, each. The cover and gasket are separate line items: CV-4 die cast cover or SCV-4 stamped aluminum cover, and either a GKV-4 composition gasket or a GKN-4 neoprene gasket. Pick one cover plus one gasket per body so the job closes up the same day you set the conduit.

32 cubic inches of wiring chamber. That is what you count against for conductor fill and splices under NEC box-fill rules, and it is why an LB body is used as a pull and splice point rather than just a direction change. Throats are smooth, so pulling large conductors through without jacket damage is straightforward.

It is an EMT fitting. The BLB-4 is built for use with EMT conduit, so it accepts the tubing rather than threaded rigid or IMC. If your run is threaded rigid or IMC, specify a threaded LB body instead; forcing an EMT body onto threaded pipe gives you no listed connection.

Die cast aluminum body, UL listed, and RoHS compliant. Aluminum is the usual pick for exterior service entrance LBs because it does not rust like steel and takes paint well. If your spec calls for a non-metallic LB instead (PVC runs, corrosive environments, no bonding path wanted), the Arlington Industries 935NM AnyBODY LB-style non-metallic body is the alternative we carry, in 2 inch threadless.

They are both LB-style conduit bodies but they are built for different raceway systems. The BLB-4 is a die cast aluminum Type LB conduit body made for use with EMT conduit, with retained stainless steel cover screws and smooth throats for wire pulling. The Arlington 935NM is a non-metallic AnyBODY LB-style body in a 2 inch threadless configuration. If the run is metallic EMT and you want a metal body, the BLB-4 is the match; if the run is non-metallic and you need a threadless connection, the 935NM is the one to look at.

Two gaskets fit the BLB-4: the GKV-4 composition gasket and the GKN-4 neoprene gasket. Neoprene is the one electricians reach for where moisture, weather, or oil is in play, since it stays resilient and seals better against the cover flange; composition is the economical choice for dry interior runs. Either way the gasket only does its job with the cover drawn down evenly on the retained stainless steel screws.

Yes, the BLB-4 ships on an order multiple of 2, with 2 per inner carton and 10 to the outer carton. Plan quantities in even numbers, and for a multi-unit or campus job the 10-pack master carton is the clean buying unit.

Both close the same BLB-4 opening. CV-4 is die cast, the heavier cover and the one to use where the body may take a knock, on a loading dock wall or an exposed exterior riser. SCV-4 is stamped aluminum, lighter and lower profile, fine for protected interior work. Cover screws on the body are retained stainless steel, so you will not drop them off a ladder.

The BLB-4 uses its own matched accessories: cover CV-4 in die cast, SCV-4 in stamped aluminum, gasket GKV-4 in composition and GKN-4 in neoprene. Those are sized to the BLB-4 body and are not interchangeable with a non-metallic LB-style body such as the Arlington 935NM, which is a different construction entirely. Order the CV-4 or SCV-4 and the matching gasket when you need a weather-resistant closure on the BLB-4.

The BLB-4 has a 32 cubic inch wiring chamber with smooth throats, which gives you a working space to pull conductors and make splices, and its overall body runs 7 1/4 inches by 7 7/8 inches with a 2 1/2 inch depth. If you are weighing it against the Arlington 935NM AnyBODY LB-style non-metallic body, that one is a 2 inch threadless design, so confirm the conduit system first and then compare the chamber you actually need.