Replace part numbers: 188-12, 188-14,41331212700. Bulb flange diameter: 19mm. Compatibility: Compatible with STIHL BG72, BG75, FC72, FC75, FR410C, FR460C, FS25-4, FS65-4, FS72, FS74, FS75, FS76, FS80, FS85, FS240, FS260, FS360C, FS410C, FS460C, HS72, HS74 HS75, HS76, HS80, HS85. Replacement Part Compatibility: This replacement bulb is compatible with Walbro carburetors including models WA, WT, WY, WYJ, WYK, WYL, WYP, and WZ that use this specific bulb size. Easy Installation: Designed for straightforward installation, these primer bulbs can be easily fitted into the carburetor without requiring specialized tools, allowing for quick and hassle-free repairs. Enhanced Performance: By ensuring a proper seal and efficient fuel transfer, this primer bulb helps in achieving smooth engine starts and reliable operation, which is crucial for maintaining the performance of your trimmer., Manufacturer: The Lord of the Tools