PART #s 550-004 and 550-005 heat exchanger protectors are made from UHMW that is slotted to replace OEM slotted protectorsSki-Doo protectors are available in 3/4" high, or 1" for added protectionPART #04-201 is made from Hyfax and has 11 5/32" mounting holesPART #LM-4120 is made from extruded aluminum, has six 13/64" mounting holes and is 3/4" tallPART #LM-4121 is made from extruded aluminum, has six 13/64" mounting holes and is 1" tallPART #LM-4122 is made from UHMW plastic and requires model-specific drilling for installation on Yamahas