WEST SYSTEM MODEL A PUMP 3:1 RATIO – For metering larger quantities of 105 Resin and 207 Special Clear or 209 Extra Slow (3:1 ratio) Hardeners. The 306-23 Metering Pump will reduce mixing time and waste on large projects. A carrying handle allows you to move the pump where the work is. Reservoirs hold one gallon of resin, one quart of hardener. Dispenses approximately 0.5 fl oz of resin/hardener per pump stroke (about 1 qt per minute).