backer rod

6. Polyethylene. it is mailnly used in expansion joints.

5.Free from erosion of acid and alkali

4.With fine elasticity and bale to endure the outside force of expansion and shrinkage

3.With no water penetration

2. Enhancing the performance of rubber gasket ,because with it ,the there sides will not be sticking and wont be formed at the rubber gasket

1.Keeping   the combined shape of rubber gasket

Function : for caulking ,maintaining the coimbined shape of sealing gasket and enchaning the performance of the sealing gasket