GMP Tools part 89031 is a 12 mm collet-style duct clamp for Tornado and comparable cable blowing machines, holding 12 mm microduct rigidly at the blower head. At this smaller diameter the duct is easy to deform or push back, so a correctly sized clamp is what keeps the air seal and the blow distance consistent. Machined for repeated field service, it pairs with the matching 12 mm duct seal to complete the inlet assembly. Specified by fiber and broadband contractors blowing small-count fiber optic cable through microduct. Millennium part #566820.