Home / Agriculture / Hydroponic 4″ X 2″ Open Trunking Pipe Hydroponic 4″ X 2″ Open Trunking Pipe Open Trunking Pipe for hydroponic system usage. The cover can be opened for easy cleaning after each harvest. Category: Agriculture Tag: Agri-Hydroponic System Related products 1″ PP Air Release Valve Hydroponic 4″ X 2″ Rectangular Pipe Elbow 90deg 4″ X 2″ Open Trunking Pipe End Cap With Outlet Hydroponic 4″ X 2″ Rectangular Pipe Socket RAINDRIP Tap Timer Anti-Insect Net