800mm MGN12 linear rail guide with 2 MGN12H blocks
There are 2 red rubber stoppers to keep the block on the rail
Threaded holes of the block 4-M3*3.5; center distance of the holes 20*20mm
It is suggested to use M3 socket head cap screws and T nuts if you fix it to 20 series EU Al-profile
Come with 2 spare balls in the package for backup