This is the Hollis Cam Bands for Tech Diving Harness Systems in Delrin or Stainless Steel Options Features: 316 Stainless locking ring 2 webbing width Number coded threading guide Velcro secure closure Quick adjust cam band with Delrin or Stainles Steel buckle locks tight securing your cylinder in position. Specifically designed for use with single tank adaptor and single tank backplate configurations. "