For the OS 120 4-stroke, it does specify an isolation mount, A Jtec mount to be exact. Unfortunatly I tried to obtain one from Jtec and was told they will not have any in the forseeable future. So I'm going to use a Dubro isolation mount. I wasn't sure about the cowl so I built my own mold and pulled my first part (epoxy/glass) on Sunday; It looks pretty good if I say so myself.