This is one of the Fluval 06 series external canister filters.
The differences between this model and the others are its size and the 306 sticker that is placed on the front. It also has FLUVAL lightly imprinted on the front casing.
Click here for the Fluval 06 series user manual.
Click here for the Tropical Fish Site's review on the Fluval 306 Canister Filter.
Click here for Fluval's website where you can find the 306 Canister Filter among others and can compare their products.