Practice your life - Do you often have such problems? Worrying about small shrimp and small fish trapped in the tank. These inlet filter cover protectors can prevent shrimp or fish from being sucked into the cartridge filter. Easy to use - Cover the sponge directly over the water inlet of the filter protection. They can easily be connected to the filter air inlet, such as filter, filter tank and other related filter equipment. Easy to clean - These aquarium filter protectors can be easily cleaned with soft brushes. Just brush them gently under running water, then the accumulated debris will disappear in seconds. Quality Stainless Steel - This strong filter guard is made of durable stainless steel and acrylic. Does not rust easily. They are robust, compact and resistant to deformation. Ideal for long term use and replacement. 4 piece set - Comes with 4 piece stainless steel filter guard. 2 pieces in white color and 2 pieces in black color. The inner diameter of the filter cover is approx. 16mm / 0.63 inch.