Hose and fittings are essential components used in a vast spectrum of industries and applications. Rubber hoses and PVC hoses are used in many general-purpose applications, from hydraulic and pneumatic systems to agricultural operations to the construction industry. Fittings, such as hose couplings and push-lock fittings, work with hose to transfer material or liquid. Fittings come in a wide range of sizes, shapes, and materials specific to a particular hose and application. Key elements to consider when selecting fittings include thread size, thread standard, and the diameter of the hose or pipe used with the fitting.