These black, high percentage rubber stoppers are low in free sulfur and have two holes to facilitate laboratory procedures. Stoppers sized as 00 have 3mm diameter holes; the size 1 stopper has 4mm holes. Stoppers sized as 2 and larger have 5mm diameter holes. Stoppers remain resilient and pliable under most laboratory conditions.

Length: 25mm

Top diameter: 26mm

Bottom diameter: 20mm