The subject articles are identified as SEAC Screen Computers/Scuba Dive Watch Computers which include part number 1600008000524A with a black and white screen, part number 1600008000525A with a black and blue screen, and part number 1600008000538A with a black and red screen. You stated that the Scuba Dive Watch Computer “displays depth, time and relevant diving information during the scuba dive.” The dive watch computer contains a liquid crystal display (LCD) screen, an adjustable backlight, and is battery operated. The subject article is designed to be worn on the wrist and is water resistant up to 100 meters. The case and the case back of the watch are composed of stainless steel and the watch strap/band is made of rubber. The dive watch computer is covered with a rubber protector. The Scuba Dive Watch Computer manages a watch mode and three dive modes that include scuba, free diving, and gauge. The watch component features a 12/24 clock with minutes and seconds, a second time setting, an option to switch between primary and secondary time, a calendar, a stopwatch, a countdown, and an alarm. The scuba mode provides management of recreational dive profiles with a Bühlmann ZHL-16C decompression algorithm for 1 or 2 mixes (air, Nitrox, and mixes with O2% concentrations up to 99%). The free diving mode displays dive/surface time and current/maximum depth. The gauge mode features a depth gauge and stopwatch for managing the dive profiles independently. The Scuba Dive Watch Computer is a multi-function device that contains time keeping/watch components and measuring components. The device displays time, depth, and diving information during the scuba dive.
[1] Please importantly note that only the relevant portion of the related is displayed above. You may refer to the said customs ruling for the entire ruling explanation.
[1]. https://rulings.cbp.gov/ruling/N322291