Review for LEGO set 6175 Crystal Explorer Sub from Lego Maniacs' Guide
“Very cool design. Comes with crystals and a working compass. Lots of transparent blue and orange elements. This sub has it all. It comes equipped with two grabber arms, one for gathering crystals, and the other for moving the crystal storage boxes. There is a cargo bay... More behind the cockpit to store crystal boxes. Three screws propel the sub through the deep water.”