It is made from Mineral Glass
New Black Color Bezel Insert for Seiko 6106-8229 and 6106-8227
These have been discontinued and are no longer available from Seiko
It is an exact fit for your Seiko 6138-0040 6138-0049 Bullhead
Y514-6009 Crown (no watch the watch is a picture in the back grand)
Tachymeter Dial Ring for Vintage SEIKO Chrono 6139-6012 6139-6013 Blue , NO Dial It is made from MineralDial Ring for Vintage SEIKO Chronograph 6139 6010, 6139 6011, 6139 6012,6139 6013,6139 6015, 6139 6017,6139 6019. NO Dial, only Dial ring Please do not hesitate to contact us if you have any further question. Please look at our other listings, If you want any kind of our items in a larger quantity, feel free to contact us. We stand by our products 100% and if by any chance you are not satisfied with your purchase, We will gladly accept returns with no