The BOSS 5.56mm Standard End Cap for 1.5-Inch Housing in black (brand part no. EC-150-556-SS-SE-BLK) is a replacement end cap for B.O.S.S. silencer models built on the 1.5-inch tube. It is the standard, non-vented design that B.O.S.S. lists for non-gas-blowback actions such as bolt guns and piston rifles. The maker notes it is a handy swap for a Chairman owner who wants to run that can on a 5.56 rifle, and the cap can go back on when the suppressor returns to .30 caliber. It weighs 1.4 ounces with a black nitride finish. This is the end cap only, so the suppressor is a separate purchase.

Key Specifications

• The caliber size is 5.56mm, the bore size of this end cap.
• The housing fit is 1.5-inch B.O.S.S. tubes only, so it will not fit other housing diameters.
• The design is a standard, non-vented cap, the plain configuration of the two caps B.O.S.S. offers in this size.
• The intended action is non-gas-blowback such as a bolt gun or piston rifle, per the maker’s listing.
• The weight is 1.4 ounces, so swapping caps adds almost nothing to the suppressor.
• The finish is black nitride, a hard surface treatment for a part that gets screwed on and off.

Frequently Asked Questions

Will this fit a 1.75-inch B.O.S.S. housing? No. B.O.S.S. says this end cap only fits its 1.5-inch tubes.

Should I choose the standard or the vented cap? B.O.S.S. lists the standard cap for non-gas-blowback actions such as bolt guns and piston rifles and the vented cap for gas blowback actions such as a traditional AR-15. For AR-10 and AR-15 rifles or other gas impingement firearms, the maker recommends the vented cap for dramatically reduced back pressure and gas exposure.

Does this include a suppressor? No. It is the replacement end cap only, for use on a B.O.S.S. suppressor with a 1.5-inch tube.

Buy the BOSS 5.56mm Standard End Cap for 1.5-Inch Housing, Black

Order it from our Lubbock, Texas gun shop for fast, insured shipping, and browse more B.O.S.S. parts in our silencers and suppressed firearms section.