Product review (5 stars): Fits ISE and some GE Disposall 3 1/8 inch
I ordered this on a whim to fit my GE Disposall, and it does - I wonder if some Disposalls are co-branded with ISE?  For anyone considering buying this, it fit my sink opening which is about 3 1/8"  diameter, or 3.08 inches on a caliper to be exact.  The splash guard matches mine exactly, and the stopper fits into the hole on the splash guard.  (Just the stopper at SearsPartsDirect.com was $24!).