LiftMaster 10-foot replacement belt, part number 41A35892. This one's specifically for older LiftMaster and Chamberlain belt-drive openers made before 2001. If you've got a newer unit, this isn't the one you want. The 41A35892 is a different belt than the 41A543414 even though they're both 10-foot. Older openers use a different rail profile and belt tooth pattern. When the belt's shot, the opener either slips, makes a grinding sound, or can't complete a full cycle. Check the manufacture date on your opener and verify the part number matches before ordering.