Patented Power Locks hold more pressure, longer. Provides 500 lb. of 1-handed force (900 lb. of 2-handed force.) I-beam bar resists twisting and bowing, allowing maximum force to be applied. Quick-Release trigger for nonexplosive pressure release. Quick-Change jaw converts quickly into a spreader. 3'' throat depth accommodates larger workpieces. Nonmarring pads grip securely and protect workpiece finish. No. 2021406N: 6'' No. 2021412N: 12'' No. 2021418N: 18'' No. 2021424N: 24'' No. 2021436N: 36'' No. 2021450N: 50''