Anddas Walbro 188-16-1 188-16 RED Primer Bulb for Poulan Craftsman 530035497 WA (20pcs) High quality 20pcs primer bulbs for Echo, Homeite, Lawnboy, Poulan, Ryobi, Ryan, Shindaiwa, Stihl and others Outside Diameter: 21mm/0.83" Height: 17mm/ 0.67" Package Includes: 20 x Red Primer Bulbs