Stens 385-904 Trimmer Bump Knob Fits Ryobi MTD 791-180814B 180814 147496 by Stens $11.47 Sold out 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Sold out PRODUCT INFORMATION Type Other PRODUCT DESCRIPTION DESCRIPTION Stens Trimmer Head Bump Knob Ryobi 791-180814 B FITS MODELS Ryobi IDC 395, 580, 580-1 and 780; Ryobi series 780R, 790R, 865R, 885R, 990R and Singer GBC2818 REPLACES OEM Ryobi 147496, 180814, 791-180814 B SPECS 2" OD x 15/16" HT 3/8"-16 LH external thread size