RING SET FOR 1275 +.020 4-RING PISTON. RING THICKNESS .0625" and 0.1562" oil ring..For later piston 19320 with 2 rings and an oil ring with the same ring sizes- keep the third ring as your second ring which should be of an oil scraper type, and usually the top 2 rings are the same so discard one of them, but check before fitting.

RA26686 and BHM1166 were the original ring set numbers for the 3 ring type