Outer materia

Natural rubber material, 25%-35% rubber contents

Bladder

Natural rubber/butyl bladder by yarn/nylon wounded

Layer

3 layers(rubber+yarn/nylon+rubber) 

Size&Weight

3#:  57-59 cm in circle;          300-325g

4#: 64-66 cm in circle;           320-360g

5#: 68-71cm in circle;           410-450g