Solid brass hardware, harness leather, installation required when you choose the install kit. FAQ: What is the difference between a standard strap and the A807ki strap? Answer: Hey good question! The sternum straps are all the same, the letters at the end relate to what they come with: A807 is the removable part of the sternum strap (die-cut leather strap with brass roller buckle and riveted brass halter snap), the A807k is the same as A807 plus rivets, washers, D-rings & die cut leather straps to allow you to install the d-rings & leather straps on your own (hole punch, rivet setter, nippers, and hammer, plus assembly, required), and A807ki is when we install it all on a pack for you here. You'll find the A807ki available as an add-on with most of our daypacks.