Self Healing Injection Ports 100pcs. Widely used in mushroom cultivation for liquid culture jars, supplemented substrate jars and grain masters.
 
Outer Diameter: 12.5mm /0.49"(approximate)
Inner Diameter: 7.2mm /0.28"(approximate)
Made of durable butyl rubber, good heat stability.
Designed for a 13mm or 1/2 inch diameter hole opening.
Package includes 100pcs X Injection Ports