Trimmer Head Bumb Knob / Ryobi 791-153066Pack Size:1Lawn-Boy 682069, Lawn-Boy 153066, MTD 791-153066, MTD 791-153066B, Ryobi 153066R, Ryobi 153066, Ryobi 791-153066, Snapper 4-2076, Snapper 7068049, Snapper 68049, Snapper 7068049YPESF 190-201, Foley/PLP 190-201, Green Meadow TBK10, NHC 207-2562, Oregon 55-803, Prime Line 7-03928, Rotary 7235, Sunbelt WE-6, Sunbelt B1WE6Ryobi 130R, 135R electric trimmers, 700R, 710R, 720R, 740R, 750R, 970R, CS720R, SS720R, Singer GT2815, GTS2816 and GTE2818; Troy Bilt TB75SS, TB475SS; Yard Machines Y28 and 2800M 1 3/4" OD, 5/16"-18 THD, Poly bagged