"This is a light duty clamp, so don't expect too much, especially considering that is costs less than a tenner. Hence, i've reviewed it as such!
I've used it for mitre joining and welding some small sections of 1" angle and box section and it does just fine. I wouldn't use if for heavy 2" box, 6m lengths or anything like that or clamp it up extra tight. If you want a clamp for that, you'll have to pay 10 times the price for a heavy duty cast item!"