The Prusa Z-Rod Constraint is a wonderful thing but its lacking a decent endstop mount. There is another derivative with an endstop mount on thingiverse but we found we broke it too easily or ruined endstops by accidentally getting glue in it.Supportless VersionI have added a supportless version (rev2) of the endstop mount that has elongated screw holes so you can make your adjustments at the endstop and not by moving the z constraint along the rod.The original enstop mount will need to be printed with support.You will need:2 x M3-14 Screws (will need shorter with rev2) 2 x M3 Hex Nuts (the tiny ones about 5mm big) 2 x M3 Washers (Optional) 1 x M4-20 Screw 2x M4 Washers 1x M4 Nut 1 x endstop 1 x 608 skate bearingYou will probably have to drill out the mounting holes on the endstop with a dremel to get the m3 screws thru the end stop.