These flexible polythene bottles allow single handed operation to accurately dispense liquid such as catalyst into an engraved calibrated output chamber. Safety cap ensures safe dispensing. 15 ml bottle dispenses 1-15ml and holds 500ml. 80ml bottle dispenses 10-80ml and holds 1000ml. Note 1ml=1cc=1mg. For large users of catalyst, as in fibreglass factory production, a Professional Wall-mounted 100ml Catalyst Dispenser is recommended.