The black phenolic resin lid has a raised ridge around the entire circumference for easy fixing and sealing, and the liner forms an ultra-tight seal by providing tight sealing protection.

Insert the phenolic resin cap into the sealing area to form a tight closure, preventing liquid leakage, carbonation and gas leakage, providing you with a good closure and airtightness for easy storage of items.

Spiral conical sealing gland is widely used for capping all kinds of soft and hard packaging bottles and tubes for daily chemicals, food, cosmetics, pharmaceuticals, etc. 28mm cap is suitable for Boston round clear amber glass planting cups. It can be used for compo tea fermentation and film developing chemicals.