MINGSWEAR

100% Sapphire Crystal Lens

Stronger than Glass 

Scratch Resistant 

7 Sizes 

18 x 1mm for Lumintop FWAA

23 x 1.5mm for Lumintop FW1A, FW3A and LM10

25 x 1.5mm for Emisar D4V2, KR4, DW4, D4K. NOTE: THIS IS .5MM SMALLER DIAMETER OVER THE STOCK GLASS 

25.5 x 1.5mm for Emisar D4V2, KR4, DW4, D4K AND KRK

25.5 x 1.5mm for Noctigon KR4 

32 x 1.5mm for Emisar D1 or Noctigon KR1

36 x 2mm For Emisar D4SV2

32 x 1mm for Noctigon KR1 but its .5mm thinner than the stock glass so you will need a thicker Oring gasket at the bezel 

What is special about sapphire crystal?

Synthetic Sapphire: A synthetic sapphire crystal or “glass” is actually not glass at all. It is a very hard, transparent material made of crystallizing pure aluminium oxide at very high temperatures. Synthetic sapphire has the same hardness as natural sapphire gemstones, but without the coloring agents that give the gems their various hues. When it is heated, the synthetic sapphire forms round masses, that are then sliced into pieces with diamond-coated saws. These disks are then ground and polished into watch crystals. (One reason sapphire crystals are relatively expensive is that the tools required to cut and polish this extremely hard material are very costly.) Sapphire (whether natural or synthetic) is one of the hardest substances on earth. It measures 9 on the Mohs scale, which is a system for rating the relative hardness of various materials. (Diamond measures 10, the highest rating.) Watch crystals made of synthetic sapphire are often marketed as “scratch resistant” or “virtually scratchproof” because they are very difficult - but not impossible - to scratch. Diamond can scratch them; so can man-made materials that incorporate silicon carbide, which, with a Mohs rating of between 9 and 10, is harder than sapphire. So, if you accidentally scratch your watch on a simulated-stone surface or a wall that incorporates some of these silicon carbide materials, it could scratch the crystal.