Our 300ml crystal polystyrene plastic glass is CE marked at half a pint so approved by trading standards. Crystal polystyrene is generally considered to be better quality than the slightly opaque polypropylene but unlike polypropylene, crystal polystyrene will crack if too much pressure is applied. This makes polypropylene a better choice for pubs and bars, but crystal polypropylene the better choice for conferences and marketing and promotional activity, not only because it looks better but because it can be printed in volume for little more than the cost thus being cost efficient. This item is lined at 300ml and is a half pint to rim capacity.