We have 4 types of tubing: 1. Black plastic tubing - use with barbed fitting and clamps 2. Kink-free tubing - uses barbed fittings and stainless steel clamps to secure - Corrugated, flexible hose which cannot kink 3. Flexible PVC - Glues together exactly like PVC with Slip fittings but is flexible 4. PVC - Rigid and glues together with primer and glue