We purchased tiles for house hold ,shopkeeper told all are best tiles of grade 1.Common person don`t know any thing about it .Contractor brought to our notice that these are 2nd class tiles .on first class tiles word premium is written & on 2nd class commercial with good difference inn rates .Shopkeeper mix premium with commercial during supply .Layman can`t differentiate .Some times word commercial is covered by shopkeeper with some stickers just to make money.Company should make some easily visible difference..so lay man can differentiate between premium & commercial.