This 5 way heavy duty box section connectors are designed to connect 25mm square tubing which has a 1.2mm tube wall thickness. The Square Tube Connectors have a heavy duty metal core which makes this a very durable and strong box section connector. No need to weld or screw to fix into position, these box section connectors hold the square tube snugly in place. 25mm 5 Way Square Tube Connector Grey