Top Diameter: 17 mm.
Bottom Diameter: 13 mm.
Soft, pliable, resilient, low in free sulfur, resistant to chemical attack.
Made of black or blue rubber.
Size numbers are molded into the top.
All stoppers are 25 mm long.
Accepts 4 mm tubing.
Developed for demanding laboratory work.

Chemistry School Lab Equipment Suppliers in India 

Ltekonline are the manufacturers of Rubber Stopper Two Holes Cork and Tubing Lab used to demonstrate engineering principles in Engineering Colleges, Engineering Schools and Chemistry Lab Equipment for Engineering Teaching Lab in Universities