OEM = 503-539002, 544 2238 02 :48mmx1.5mmx1 WAS TM572499 SAME AS TFHS6148, THH31061T FOR PISTON RINGS USE TLHU0039
Note: There were two types of pistons available on Husq. 61 saws, a Windowed piston and a non windowed piston for closed port vs open port cylinders. This is a windowed piston for closed port cylinders. Please check yours before ordering.