Primer Bulb / Walbro 188-12-1 Pack Size:1 ECHO 12318140630, HOMELITE 01201, HOMELITE UP04802, HOMELITE UP-04802, MCCULLOCH 225834-00, SHINDAIWA 20036-81670, STIHL 4133 121 2700, WALBRO 188-12, WALBRO 188-12-1, WALBRO 188-14, WALBRO 188-14-1 BYNORM 386-300, DEALER CHOICE 33-1205, FOLEY/BELSAW 5980099, J. THOMAS JT-5740, LASER 48015, LASER 40341, OREGON 49-020, PRIME LINE 7-02385, ROTARY 9478, SUNBELT WAL-188-12 WALBRO WA, WT, WY, WYJ, WYK, WYL, WYP and WZ carburetors that require a 3/4' OD x 9/16' HT primerbulb Not compatible with greater than 10% ethanol fuel , OD: .721 ', ID: .579 '