Hose couplings are used to firmly and reliably connect hoses to various types of water and pressurized air outputs. They may be found in a variety of commercial, industrial, and household contexts. Solid (flour, sugar, etc.), liquid (including chemicals and hydraulic oils), or gaseous media can flow through them (including compressed air).
A male adapter has the threading on the outside of the hose fitting, while the female adapter has the threading on the inside of the hose fittings.