These clamps were manufactured by Wittek Mfg Co for the military as per MIL-DTL-8783. They were used for aircraft installations of duct, hose and flex tubing. The minimum diameter is 5.75”. The maximum diameter is 6.12”. The nominal diameter is 5.94”. Band width is 0.625”These clamps were used to secure the Air cleaner hoses on the M746/M747 Ward LaFrance Tank Retriever.