Features: 
Seal design. Forcing filtration system, more thorough filtration 
Ultra-quiet design. It comes with three thick cotton biochemical pads. 
Circular design makes cleaning without dead spaces in the aquarium/ 
Dual use with freshwater and seawater 
Easy installation and use 
Safety using and beautiful style.
Model: HW-603 - Larger Version of HW-602
Size: As photo showed
Volume: HW-603 2.8L
Hose Adapter: HW-602 12mm/ HW-603 16mm
Water pipe: NO 
Water-pump: NO
Package includes: 
1 x SUNSUN HW-602 Outside Pre-Filter; 
3 x Biochemical Cotton