Designed for Polyurethane or Nylon tubing. Quick and Reliable connections. Reusable: Multiple connections/disconnections. Convenient elliptical sleeve configuration. Metallic body made of non-corrosive, non-contaminant Nickel-plated Brass. Specifications: Fluid Type: Air, O-Ring: NBR (Acrylonitrile butadiene rubber) Metallic Body: Nickel-plated Brass, Plastic Body: PBT (Polybutylene terephthalate), Packing: NBR (Acrylonitrile butadiene rubber), Back Ring: POM (Polyoxymethylene plastic), Lock Claws: Stainless Steel Collar: Zinc Alloy, Sleeve: POM (Polyoxymethylene plastic).