Item Type: Primer Bulb_x000D_Material: Rubber_x000D_Mouth Outer Diameter: Approx.18.5mm / 0.73in_x000D_Height: Approx.14.6mm / 0.57in 1Replacement Part Number: The replacement part number is 123?181?40630 or 123?181?09560, perfectly compatible. 2Rubber Material: The primer bulb is made of high quality rubber material, which is wear resistant and durable, soft and has good performance. 3Perfect Replacement: Practical replacement accessories, easy to install, can replace broken or old parts, perfect replacement. 4Perfect Match: Suitable for Walbro 188?12, 188?12?1, for Stihl 41331212700, for McCulloch 22583400, etc. 5Good Workmanship: Small size, light weight, the outer diameter of the cup mouth is 18.5mm, the height is 14.6mm, and the size is standard.100 x Primer Bulb