Can give E6B2 OVW encoder, such as can be fixed on the market through 20 type, diameter, 38, 40 of the encoderOptical axis comes with M8 screw holes, you can add the length of the shaft according to your actual useUsage:Industrial:MetalworkingStandard or Nonstandard:NonstandardUse with encoder to measure velocity and positionIt have high resolutionStructure:Single-side BracketColour:Silver & GreenMaterial:Aluminum alloy + polyurethaneSize:Overall Size:14x9..8cm /5.51x3.70x1.88 Inch( L x W x H), Inner hole size:6mm, Perimeter:200mmPackage Contents:1 x Encoder Mounting Bracket3 x fixing screws2 x locking screw1 x Encoder wheelOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.