详情

1. Watch case back crystal, these crystals are widely used for watch case back. Usually our tolerance for this model is +/*0.*3mm for diameter, +/*0.*5mm for thickness.
2. This kind of perfect optical sapphire crystals have excellent transparency in wide spectrum , high hardness (about Mohs 9) , the chemical purity is so far as to *9.**5%,  and precise orientation of optical axes . 
3. Any customized shape and size is welcome, we will produce it strictly according to the technical drawing from customers.