S92mech is correct about the dual CVR/FDR combo. He is also correct about the installation. One is standard mounted in the LH avionics rack and the second optional equipment mounted above the cargo ramp area transition section just before the tailboom.
I must commend the Canadian TSB and the crews working the recovery efforts. Their speed and compassion is to be commended. The response and efficiency is beyond reproach. Thumbs up to the ROV operators!
Matt and Tim, I will miss you both and remember you always!