Brownells 5.38" x 3" x 1" AR Lower Receiver Vise Block, White

The heavy-duty vise block absorbs all clamping force, ensuring that your expensive lower receiver remains free from scratches, distortion or any other damage. To use, insert the block into the magazine well as you would with a standard magazine, then secure the opposite end in your bench vise. The magazine catch locks onto the block, providing a safe and secure hold on the rifle for assembly, disassembly, cleaning or repair. The double-ended design is compatible with ArmaLite AR-10, Bushmaster .308, DPMS Panther LR-308 and Remington R-25 models. It is not compatible with Rock River Arms lower receivers. The block is machined from rugged, durable and chemical-resistant Delrin polymer, ensuring it will not mar or scratch the weapon's finish. Precision-engineered Delrin polymer material Compatible with the majority of AR-style .308 rifles, excluding those manufactured by Rock River Arms