Scubapro Black Mantis (M1) Scuba Diving Computer Wrist Watch Targeted to recreational and technical divers as well as CCR divers and freedivers. Durable Black Tech coating delivers excellent protection from scratch and saltwater corrosion. Predictive Multi-Gas ZHL8 ADT MB algorithm accommodates three gases (21-100% O2). PDIS (Profile Dependent Intermediate Stops) calculates an intermediate stop based on N2 loading, current and previous dives and breathing mixes for safer diving. Microbubble levels let you adjust the level of conservatism in the algorithm to match your experience level, age and physical conditioning.