the missing part of the D9 MK2 kit. This will place a second wheel on the iide frame, making Z more solid. You can reuse the M3 screws and spring to mount back onto the bracket. Two additional V wheels will be needed and up to a 24MM M5 for the wheel mounting. Print two Dual Z for the Z axis. Added 2/10 X-Y dual This will work for both X and Y axis two are needed for Y and one for X axis. The hole depth is 6MM, under 18mm screws work without a washer.