Prusa I3 MK8 part upgrade

This is my all think I made for my prusa I3 MK8 dual extrudeur modif.

For the chain, I buy it on Banggood, It's 10mm x 10mm chain
http://www.banggood.com/10-x-10mm-Plastic-Cable-Drag-Chain-Wire-Carrier-Length-1000mm-With-End-Connectors-For-CNC-p-995511.html?rmmds=myorder