The Clifford & Snell YO3IS is a 100 dB (A) Intrinsically Safe Audible Signal. The YO3IS is designed for use in hazardous environments.
The YO3IS must be used in conjunction with an approved Zener Barrier or Galvanic Isolator. The Clifford & Snell YO3IS is only to be powered via a correctly rated Zener Barrier or Galvanic Isolator. To power the YO3IS without the correctly rated barrier could damage the unit and so void any protection ratings.