TJ Longda 50 Pieces Stainless Steel Single Ear Hose Clamps size 13/16" or 21mm 1. Materials: Stainless Steel Band UNS S30400. 2. Smooth inner circumference for 360 degree uniform seal. 3. Precise tongue-in-groove seamless design. 4. To use in the industries like automotive, food and beverage, and so forth. 5. Not for Pex Plumbing.