Grand seiko watch spring drive 8 day power reserve sbgd001 the grand seiko spring drive 8 day power reserve watch is a completely new and innovative concept from grand seiko watches the first thing that you will notice is the diamond dust dial housed beneath the sapphire crystal glass which is inspired by the glistening snow that is found in the nagano region where the watch is born the unusual shimmering effect is stunning but subtle enough that it doesnt distract you from the rest of the