The B5 Systems Aluminum Trigger Guard is machined from 6061 aluminum with a type III hardcoat anodized finish. This enlarged trigger guard allows for gloved use with your rifle and still maintains the swing down function if you need it. This drop-in upgrade is compatible with AR-15 or AR-10 lowers and is simple to install.Features: 6061 aluminum Drop-in upgrade compatible with AR-15 and AR-10 lowersB5 Systems believes in building products that favor function over flash. Every component is thought out and tested to ensure every product functions as intended. If you are building a serious rifle that you want to be able to trust, you can't go wrong with B5 Systems.