Raised polished steel coloured numerals and markers, with matte black background
This insert has a slopping design.
Hence these crystals are required for a better fit:
Sapphire Flat - Type E - Seiko SKX007
Sapphire Double Dome - Seiko SKX007
Sapphire Double Dome - No Bevel Edge - Seiko SKX007
Seiko SKX007, SKX009 & SKX011 series
Seiko 5 SRPDxx series (SKX007 replacements)