based on my experience this clamp set was a complete disappointment. Although the price was appealing, the quality was lacking... The plastic material was flimsy and unable to hold the weight of my workpiece. The set was advertised as "Industrial and Scientific," BUT in reality, it was not up to the standard. The only positive aspect was the variety of sizes included in the set. However, that was not enough to make up for the lack of strength and durability..