OSE CNC Rail Motor Mount.Designed to fit outriggers with a width of 3" or a rail type system that already have the rails installed. See picture 4.Fits 36 and 40mm diameter motorsSpecs:Length: 61mm (2.40")Width: 75mm (3")Height: 38mm (1.50")Weight: 51 g (1.8Oz)Motor Screw Spacing: Approximately 25mm (1")