Mar 26, 2021 · Six Syringe Filters for Mushroom Spawn Jars. $ 8.65. Rated 5.00 out of 5 based on. 1. customer rating. ( 1 customer review) Mushroom Spawn Syringe filter (13 mm diameter, 0.22 ?m). Perfect for grain spawn or liquid culture jars! Our 13 mm syringe filters are easy to use, reusable, and ideally suited for the home mycologist.