Light Doctor Disc for the 8 hole light disc. Be sure you have the correct part for your pool application. First, make these measurements for your pool.Measure from one hole directly across to the opposite hole, this is measurement “A”.Measure from one hole directly to an adjacent hole, this is measurement “B”.Compare your measurements to this table and determine which disc you need.Disc NumberMeasurement “A”Measurement “B”TLD10D11 3/8”3 1/2”TLD10QND9 15/16”3 1/16”TLD8D10 1/2”4”TLD6D5 5/16”2 7/8”TLDMDD7 1/8”2 3/4”TLD6SRD6 3/4”3 3/8”
