It's only an adapted holder for the endstop of the Z-axis. I use the great adjustable Z-EndStop-XMotor.stl of enrico_19 (thanks a lot for this idea!) to switch. Here the original link: http://www.thingiverse.com/thing:542892 For the lower bracket it was hard for my little printer to put another adjustable part. Now these two things are like a fixed and a loose bearing.The material is ABS. The temperature is for the extruder 235°C to 230°C and for the bed 120°C. Thickness of each layer is 0.2 mm. No support material needed. Like my other things, here the same sentences ;-) If you like it and you can downloaded in other formats under following link: http://a360.co/1LiWiIO You want to improve something? Then your welcome to modify it. Please leave me a short message and I'm going to send you an invitation.