The Fittings | Siphon Plug (5x9x20 mm) is a small tapered rubber plug used to seal siphon ports and drain openings on VTA gear pump assemblies and associated distillation system plumbing. It prevents air ingress and fluid leakage at open siphon connections during operation and maintenance. An inexpensive consumable replacement part for VTA VKL and VKS series distillation systems, sold individually.