This is a mount for the Logitech C270 Webcam on the X-Axis Extrusion of an Ender Switchwire Conversion. I guess it would work on the original Switchwire as well. The screw which clamps the x axis idler block on the left is used for mounting. The original screw is 16mm in length and you will need one which is at least 2mm longer. For Mounting The c270 on the Arm you will need another M3 screw, you can use the 16mm screw you took out before or any other one with a similar length  :)