Accuracy
How many seconds a day your watch gains or loses, heard through your phone’s microphone.
Zelos · Swordfish 300m Diver Seiko NH35 Cobalt Blue
ChangeSwordfish 300m Diver Seiko NH35 Cobalt Blue
Somewhere quiet, lay the watch caseback up on something soft. Rest the bottom edge of your phone on the caseback and keep both still.