When checking important data while diving (depth and air pressure), a diver usually has to look at their wrist or console display instruments to do so. When a diver's hands are occupied or when visibility is low, keeping track of his or her gauges may be difficult. Learn these essential skills for setting up your Shield display & Visor Light with your Neptune Space Full Face Diving Mask. With the SDVL, the depth and pressure data are comfortably displayed on the right and left sides of the Neptune Space visor. These two displays are accompanied with visor lights installed in the visor top. The depth and pressure displays are activated the moment the diver enters the water. The visor light (made of 6 in-line LEDs) is easily activated by a switch on the right side of the mask and incorporated in the surface air valve set.