These hose clamps are made by Ideal Tridon. They are also what Flexfab sends you direct form there factory.

Ideal Tridon
Part Number: 6516E
Flexfab
Part Number: 2582-0016
Size: #16
3/4" - 1-1/2" I.D.
19mm - 38mm
Material:
Stainless Steel
Qty: 10pcs

2582 / 65E SERIES: Lined Worm Gear Clamps
Recommended for Silicone Coolant and Heater Hoses

Specifications:
• All 300 grade stainless steel lined worm gear clamps
• Hex Head: 5/16”
• Band Width: 9/16”
• Resists salt water and may be used in marine applications
Applications:
• Recommended for silicone coolant hose, heater hose, marine, and silicone tubing

This is in stock and ready to ship. We ship Mon-Fri if your order is placed before 3:30pm Central time.