Couplers. Being a part of single shut-off couplings [air-line couplings] sv 10 are specifically designed for compressed air, air powered had tools, shop air application, water, liquid, steam, gas and other general industrial applications. Single shut-off couplings are used to connect just pull back the sleeve and push the coupler on to the adapter and release the sleeve. To disconnect, pull again the sleeve back to separate the coupler and adapter. The valve automatically opens on connection and closes on disconnection. Salient features single shut-off couplings are as follows: