This Bundle has two items: the OASE BioMaster Thermo 850 Canister Filter w/ Heater & the OASE CrystalSkim 600 Skimmer. The OASE BioMaster Thermo 850 Canister Filter is perfect for marine and freshwater aquariums. The BioMaster 850 boasts 4-stage filtration in a compact design. The biological, mechanical, chemical, and prefiltration all work together to provide your aquarium with optimal water quality and clarity. It features a built in 400 watt heater. The CrystalSkim 600 takes care of the one type of filtration canister filters are not good at—surface skimming. It effectively frees the aquarium surface of biofilm, floating plant debris and other substances. It eliminates any biofilm from the water's surface. Removing biofilm is important for proper oxygen flow in an aquarium. Designed to catch even the finest plant debris that are almost impossible to remove with a net. The EasyClean prefilter module can be removed separately from the rest of the filter for simple cleaning and to extend the life of your filter. Dimensions: 9.4" x 9.4" x 22.0" Tall. For external installation. Suitable for aquariums up to 225 gallons. The MarineAndReef Aquarium Cleaning Towel is a durable, lint-free microfiber towel. 19" X 15".