Note: there are two versions of the switch bracket. Choose the longer one if you have the newer endstop switches with wheels on the arms. Note: this part fits the 8" i3v. The 10" printer has longer X extrusions that block the screw unless you trim the excess length. This is an adjustable Z endstop that uses an inexpensive micrometer head to make precise adjustments to the Z axis. See the instructions for assembly details. If you don't want to use a micrometer head, check out my screw-adjustable Z endstop: http://www.thingiverse.com/thing:336665 Or my Z-probe servo mount instead: http://www.thingiverse.com/thing:335632The micrometer bracket clamps around the micrometer head with an M3 screw and nut and mounts to the underside of the lower X extrusion using an M5 screw and T-nut from the MakerFarm kit. The switch bracket mounts to the right side of the right Z extrusion, also with an M5 screw and T-nut. The switch is mounted with two M2.5 screws. The holes are sized for direct tapping to M2.5, or you can force the screws to cut their own threads, drilling first as necessary. Inexpensive micrometer heads are available via eBay. http://www.ebay.com/sch/i.html?_nkw=0-25%2A0.01mm+Micrometer+Head Note: there are two versions of the switch bracket. Choose the longer one if you have the newer endstop switches with wheels on the arms.