This LBE Unlimited buffer tube (brand part no. MBT04POS) is a mil-spec-diameter receiver extension with 4 positions for an adjustable stock, made entirely in the United States alongside LBE’s other AR components. It’s the housing for the buffer and buffer spring, and it provides the mounting rail an adjustable stock rides on. This AR buffer system part is sold on its own, separate from the buffer and spring.

Key Specifications

• Built to mil-spec receiver extension dimensions.
• Offers 4 positions for an adjustable stock.
• Made in the United States.

Frequently Asked Questions

Does this include a buffer or spring? No, this listing is the buffer tube itself; a buffer and buffer spring are sold separately.

Will my adjustable stock fit a mil-spec tube? Most adjustable AR stocks are built for either mil-spec or commercial-diameter tubes — confirm your stock is the mil-spec variant before ordering this tube.

Buy the LBE Unlimited Mil-Spec 4-Position Buffer Tube

A solid mil-spec buffer tube is the foundation for any adjustable-stock upgrade down the road. Order it from our Lubbock, TX gun shop for fast, insured shipping.