3 x U bolts and M3 nuts for holding Prusa i3 Mk2s Y-axis linear bearings. (http://www.prusaprinters.org/original-prusa-i3-mk2s-release/)

http://www.ebay.co.uk/itm/201966264898

These bolts will hold the bearings more securely than zip ties which can loosen over time. This item is apparently only available if you have already purchased the Prusa i3 from the Prusa store, and they are not a standard item, so I got these custom made and am making these available to those building their own - AND cheaper than the Prusa store!

Dimensions:
Rod diameter - 3mm
Hole centres - 20mm
Length - 30mm
The bolts and threads are long enough for those using thicker material for base plates. If you are using the original 6mm thick aluminium base plate you will need to trim the threaded ends with a hacksaw.