This multi-use plastic tank is ideal for temporarily holding small fish, invertebrates, or new introductions to your aquaria. Other suggested uses are filter media trays or for planting aquatic plants. The rustproof metal hangers can be bent to clip over the top of the tank. Approx. dimensions are 150mm W x 140mm L x 130mm H. The holes on the base, rear, and sides are approx 1.5mm x 1.5mm