Description the proof nautilus is a slim rfid-blocking wallet built on an aerospace-grade aluminum frame in navy blue gunmetal, with midnight blue full-grain leather. It holds up to 25 cards inside the frame and 20 folded bills under the rear strap, at 49.5 G. The nautilus ships with the nickel bolt upgrade included. How it carriescards sit inside the aluminum frame. Rfid-blocking material is built into the interior. A pull strap on the front fans the cards out, and an elastic cash strap across the back holds folded bills. Protected by u.S. Patent no. 12,604,959 And u.S. Design patent nos. D1,138,157 & d1,138,158. Covered by proof's lifetime warranty: if you damage or lose the wallet, we will replace it. Spec size: 3.75 In h x 2.25 In w x about 0.5 In thick, depending on card load weight: 49.5 G frame: aerospace-grade aluminum, navy blue gunmetal finish materials: midnight blue full-grain leather capacity: up to 25 cards and 20 bills rfid-blocking included: proof stainless steel multi-tool, which fits the wallet bolts nickel bolt upgrade maker: proof u.S. Patent no. 12,604,959 U.S. Design patent nos. D1,138,157 & d1,138,158 warranty: lifetime, covering damage and loss