Review 2: ORSA Quartz Chronograph Miyota OS60
The Case Back
A bit hard to see in this picture below, but the case back is really high polish. You can easily use it as a pocket mirror. Time will tell how much the nylon will be able to "work" on that polish after a longer period of wearing the watch. I am fussy about scratches, thus I will always clean the case back after a short period of wearing. If there is dust between the nylon and case back, that dust will definitely reduce the high gloss of the back.
The case is screwed with the 6 grooves that you find on most watches today. Opening it will not be difficult at all, the case has no exotic shapes that would block the use of a normal case opener.
The case back's inscriptions are: ALL STAINLESS STEEL - 100 M WATER RESISTANT - SHOCKPROOF with the big stylized ORSA logo in the center. As with most manufacturer, that means the crystal is mineral. It is quite normal for manufacturers to omit any crystal information on the watch back unless it is sapphire. I do not criticise the mineral crystal at all. I personally find mineral to be a great crystal material. I am careful with my watches and if I should ever scratch that crystal, it will be very easy to find an inexpensive replacement crystal.