The ideal Claning Tool for freshwater and saltwater aquariums. Progessional Grade. Handles are made with durable fiberglass to provide the proper leverage and resist corrosion for a lifetime of use. Each handle is topped off with an ergonimic grip that comfortably fits in the palm of your hand. ProScraper II models come with all three replacement blade styles to determine which works best for each cleaning job. Blades are stilll interchangeable and replaceable so cleaning can be done with that perfect edge. ProScraper II heads are also interchangeable and can be moved from the long handles to shorter handles. For hard to reach areas, extendable units are says to adjust the handle lenght with a simple twist.