*The speaker, with the cap fastened securely, has a water-proof specification of IPX7 as specified in “Degree of protection against water immersion” of the IEC60529 “Ingress Protection Rating (IP Code)” IPX7 equivalency. The speaker has been tested and maintains its operability when gently submerged in water to a depth of 1m and left for 30 minutes. The dust proof specification of IP6X as specified in “Degrees of protection against solid foreign objects” IP6X equivalency: The speaker has been tested to and continues to block dust after stirring for 8 hours in a testing device which contains dust particles that are up to 75 μm in diameter. Shock-proof includes SRS-XB23 and SRS-XB33 only . Shock tested using MIL-STD 516.8 testing standard, dropped from a height of 1.22m on plywood of 5cm thickness. Rust protection capabilities have been independently tested by Sony Corporation by submerging the speaker in seawater (seawater component 37.5g/L) then stored in a test room at a constant temperature of 60°C and 80% humidity for 96 hours.