Features: The Water Pipe Clamp can fix the water pipe to protect the fish for tank body from abrasion.Adjustable width design is suitable for most aquariums.Suitable size, doesn'for t need much space, you just install it on the walls of the aquarium.Easy to install with screws,which is convenient to use.Two sizes for you to choose.Specifications: Material: Aluminum AlloySize: S/LS-Approx.3.6x2x1.1cm/1.41x0.79x0.43inL-Approx.4.1x1.1x2.4cm/1.61x0.43x0.94inInner Diameter of SizeS:14.5mm/0.57inchInner Diameter of SizeL:18.5mm/0.72inchSizeS Fit for :4-10mm GlassSizeL Fit for :5-12mm GlassPackage Includes: 1x Water Inlet Outlet Pipe Holdernote: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.