Our Bike Cup Holder and Cell Phone Holder Combo features a black polyurethane skin, stitched to a black polypropylene cup holder/cell phone holder. Also, has a keyring holder as well. Comes with a black plastic side mount with hex bolt (4mm) fastener. The inside of the cup has tabs to keep your drink tight over them bumps. Drain hole located at the bottom for any condensation build up. This can be mounted in front of the handlebar or behind (photos show front mount). Mount compatible with 22.2mm handler bar. THE ULTIMATE BIKE CADDY - ENOUGH SAID!!! Cell Phone Slot Size is 3-1/2" at the top and tapers down to 3-1/4". This means that some cell phones will not fit with large cases, like the thick OtterBox. ALLEN KEY NOT INCLUDED.