This insulated clamp holds reaction kettles and lids together firmly. Three spring-activated clamping arms with stainless steel springs apply just the right tension. Available in two sizes. The smaller one has an inside diameter of 125 mm (4.92") and is used with 500 to 1,000 mL kettles. The larger one has an inside diameter of 142 mm (5.59") and is used with 2,000 to 4,000 mL reaction vessels. Glassware not included.