IP rating instruction
IP (or "Ingress Protection") ratings are defined in international standard EN 60529 (British BS EN 60529:1992, European IEC 60509:1989). They are used to define levels of sealing effectiveness of electrical enclosures against intrusion from foreign bodies (tools, dirt etc.) and moisture. The SP11, SP13, SP17, SP21 and SP29 connectors are all IP68 connectors, threaded coupling.