Metal bellows element rails constructed into a square or rectangular shape utilising single or double mitre corner welding, and fitted with flanges or flat bar weld ends. The joint can be fitted with internal liners, external covers and movement control hardware.

This type of joint is used primarily to absorb thermal expansion in low pressure, high temperature air and gas ducting.

Suitable for axial compression.

Manufactured to the guidelines laid down in the Standards of the Expansion Joint Manufacturers Association Inc. (EJMA).