Round threads
Assembly together with plastic dowel, more convenient to install and replace. Special threads make it strong

We produce high strength spear bolts for tunnel construction. Shapes and dimension, specifications according to customers requirements.

Their specilality is round thread, with higher strength to anti-pulling out. We produce them by hot forging and rolling instead of machining, which provide higher quality and stand

We provide Zinc plated( yellow and blue and white), hot dip galvnized finished.

Packed in Europe type wooden cases.