IN checkvalves are compliant with the regulation of NF Antipollution brand. According to the EN 1717, these EB type checkvalves are incorporated in a device, and guarantee a drinking water protection against a risk of pollution from a fluid of category 2. The design of IN checkvalve is an advantage for OEM application with side-connection (as gauge connection). The O-ring can be mounted first and secondly the checkvalve itself. In this way the O-ring will not be damaged by sharp edges of the side-connection.