The belt used in the Electromaax kits is a J or "Jason" belt in a 10 groove design. The numbering designation for these belts is inches X 10. So a 33" belt would be a J330 or 33" X 10. The J360 shown in the picture is a 36" belt.


These belts are NOT normal belts you will find at an automotive store and need to be special ordered. They are easy to find and Electromaax or another source such as Motion Industries can get them for you.


It should be noted that Electromaax sends you TWO belts in the kit. However if developing the kit the size they send you may not be correct. Best to collapse the alternator to it's shortest belt size than wrap a tape measure around it to know what you'll need. Once the pulleys were installed I did this and discovered I had 32.5" path around the pulleys. I ordered a 33" belt as opposed to the 36" belt they had sent me and all was good.


If going off cruising I might invest in a third or fourth belt as these Jason belts are NOT going to be easy to find in remote locations. No one in the entire state of Maine had one in the size I needed. It was four days to get one from Electromaax and they had sent it out the very next morning..


I know why they use this belt, and that is because it can handle a lot of HP. It would however be nice to have the option, on alts under say 140A, to have an standard automotive belt option you could grab at any auto-parts store..