Opteka Hot Shoe Three Axis Triple Bubble Spirit Level for Sony Alpha & Minolta Maxxum Digital SLR Cameras (Reverse Hot-Shoe Mount) Spirit Level / Bubble Level for Camera's hot shoe Easily identify if your camera is set up level on a tripod 3 Axis = precise leveling Fits Sony Alpha/Minolta hot shoes only. Dimensions of bottom plate (that slides into the hot shoe): 17mm / 11/16th in