PODOY (Pack of 5) Primer Bulb Pump For Stihl FS46 FS45 FS55 FS40 FS40C FS50 FS90 Package includes 5pcs primer bulbs Fits stihl FS46 FS45 FS55 FS40 FS40C FS50 FS90 trimmer Replace ZAMA 0057003 0057004 0058001 Size: Bulb height: 0. 75"(19mm) Bulb flange diameter: 0.85"(21.6mm) Bulb diameter: 0.725"(18.5mm) non original aftermaket replacement parts