Also known as manifold flange fittings, these have a clamp-together design that lets you access your line for routine maintenance. Connect the flanged end to another quick-clamp fitting with a clamp and a gasket (all sold separately). Fittings are polypropylene, which resists a wide variety of acids, solvents, and other harsh chemicals. The fittings won’t deteriorate when exposed to the damaging effects of ultraviolet light, so they’re suitable for outdoor use.

To prevent leaks in threaded connections, apply a sealant to the male threads. Threaded connections can be taken apart as needed for maintenance and repair. For metal threads, use PTFE tape. For plastic threads, apply a non-hardening, plastic-compatible sealant. Tape or sealants with PTFE are not recommended for plastic-to-plastic connections. When making a threaded connection be careful not to overtighten the threads. To prevent cracks and leaks, finger tighten the fitting, then wrench-tighten one to two turns.