Resin Glass is a clear plastic material used mainly in sports and affordable watches. Compared to mineral or sapphire glass, it is lighter and less fragile, better able to withstand shocks and does not crack, but is more susceptible to scratches. Small scratches can usually be polished out with a special paste (e.g. PolyWatch), which extends the aesthetic life. The material may yellow slightly over time due to UV ageing. It does not affect the watertightness of the case - this depends on the construction and the seal. Suitable for outdoor, fitness and work environments where light weight and ruggedness are important, and less so for formal wear where customers typically prefer higher scratch resistance.