These replacement impeller kits are for use with the Aquascape® AquaForce® line of pumps (2012 models and later). SKU UPC Code Compatible Pump 91115 742575911151 AquaForce® 1800 91081 742575910819 AquaForce® 2700 91116 742575911168 AquaForce® 3600 Manufacturing impellers often includes trimming on a lathe to achieve balance and/or testing to ensure quality. Consequently, many new impellers appear used. Our impellers are brand new; any wear is due to the manufacturing process. Tip: When changing an impeller, a frequent reason for problems is mineral build up way down inside the impeller housing which causes wear and tear on the impeller and friction against the impeller which can cause overheating and intermittent operation. We strongly recommend cleaning out the well which houses the impeller with vinegar and an old toothbrush to eliminate mineral build up before installing the new impeller.