RuuviTag Pro has been professionally laboratory tested and certified for IP67, IP68 and IP69K.
IP67 tolerates wet condition only temporarily. It can be used outside as long as the breathing membrane will not stay wet more than 30 minutes.
IP68 certification ensures that RuuviTag Pro  will function in water depth of up to 50 meters for 24 hours.
IP69K means that the unit has undergone a challenging set of tests to ensure that it offers protection against penetration of high pressure and high temperature water of 80 °C.