1With nylon screw to tighten, suitable for glass within 19mm. 2When changing water and cleaning water plants tank, tool rack can be fixed on the tank edge, easy to take and put tool, convenient for operation. 3Lightweight and compact size, easy to carry and store. 4Made of good acrylic material, good light transmittance, strong impact resistance, not easy to damage, practical. 5Wonderful tools rack for water plants tank.