Hose couplings are used to connect two hoses together or tap into a water source or hosed appliance and include coupling types made of brass, plastic or composite material in various fittings such as a cam and groove, express and Hozelock, which are all used for liquid and garden applications. Other coupling types are utilized with high pressure hoses like those used in firefighting, compressed air or steam or sanitary fittings used in the brewing or alcohol.
The three main types of household and gardening fittings are brass, plastic and nylon polymer composite couplings. The brass types are heavier and more expensive. They come in both the female and male adapter. The female end features the threads inside while the male end has exterior threading.
Plastic couplings are similar in design and durability to the brass counterparts but are less expensive. They can withstand various levels of water pressure and are ideal for home and garden use.
Couplings made with nylon polymer composites are the compromise between plastic and brass, not quite as expensive or heavy as brass but not as light or affordable as plastic.
All three types of couplings are effective, durable and affordable. A plastic coupling costs a few dollars while a brass fitting can be purchased for several dollars with a composite coupling's cost falling somewhere in the mid-range of the two.