The TopStop™ cover is engineered to snap securely onto most AR-15 upper receivers and is an indispensable accessory whenever the upper and lower are stored or transported separately. It fully seals the rear of the upper receiver, preventing lubricating oils, carbon, and debris from leaking into your bag or case. It also keeps the bolt carrier group and charging handle locked in place, eliminating the risk of them sliding out during movement. The TopStop™ comes in several colors, but we offer it exclusively in yellow because it’s highly visible and easy to identify—especially in high-stress situations when fast removal matters.
Molded from an exceptionally strong, solvent-resistant polymer, the TopStop™ is built to withstand harsh use and chemical exposure. It’s the ideal solution for storing or transporting spare uppers—especially in low-profile bags where a broken-down rifle is required.
The TopStop™ cover can be easily modified to fit non-TDP upper receivers, including platforms like the LMT Defense Monolithic Upper. Using a progression of sandpapers (80, 120, and 180 grit), you can quickly achieve a smooth, precise finish. This straightforward customization allows the TopStop™ to mate cleanly with virtually any non-standard upper, ensuring a snug, reliable seal against the receiver.
