Tpwtm master shaker from the protein workstrade is a high quality sports supplement bottle moulded out of heavy duty plastic with a tight fitting screw lid and secure flip top for easy drinking it is the ideal shaker bottle for mixing super smooth protein shakes and other powder supplementsr it contains a stainless steel ball for consistent smooth mixing it has a clearly displayed measurement gauge on the shaker to ensure you can correctly measure out the required amount of liquid requi