This design is for a brush holder used for nozzle cleaning which mounts onto the ender s1/s1pro's  heated bed cable. 

There is a version for use with threaded inserts and screwing straight into the plastic. 

Recommend using PETG/ABS/ASA at 100% infill and 0.2mm layer height. 

Requires two M3x6mm screws to join the two parts and one M3x8mm screw for the clamping portion.