Tough top screen covers provide security when housing animals in aquariums. Good for 30 gallon aquariums. Ingredients: Metal. Covers Are Durably Constructed For A Corrosive-Free, Black Woven, Welded-Steel Wire With A Steel Rim. Dimensions - 36.38 X12.69 X0.75 Size Is 12x36 (Color: BLACK; Size: 36X12)