Jill Heinerth and Karl Shreeves at Ginnie Springs resort, High Springs, Florida, USA. Jill, noted CCR diver, tec diver and underwater shooter (Heinerth Productions, intotheblue.com, rebreatherpro.com) took PADI Technical Development Karl Shreeves through training and certification as a CCR Cave Diver. Karl qualified on the VR Technology Sentinel, one of several CCRs on which Jill is qualified to dive and teach.
TecRec Blog 
It is intotheplanet.com. My oops, sorry. Karl