From the Manufacturer
Ideal for woodworking, laminating surfaces, carpentry, and craftsmen. Unique, spring loaded rotating heads slide easily over virtually any thickness materials. Universal edge gluing clamp is light weight. Large plastic swivel end cap provides scratch protection. Heavy-duty galvanized steel threaded spindle provides positive clamping pressure. Molded wooden and painted handle fits comfortably in your hand. Rotating heads are rubber lined for scratch resistance and non-slip feature. Frame made of aluminum die-cast materials for superior strength. KF-4 designed to clamp materials 1/4 to 3-1/8 inches thick.