This is a replacement plate for Arca compatible tripod quick release system. Just add a Flat Head Phillips Machine Screw
1/4"-20 Thread, 3/4" Length and you are ready to go. http://www.mcmaster.com/#91771a540/=wxbpeo

Also includes an ergonomically contoured version so I could keep it attached and grab the horizontal battery grip on my camera base without poking my hand.