Device for closing an end of a tube having an axial direction (a), such as a water supply tube, said device comprising: - a closing element arranged for being in contact with an outer surface of said tube , said closing element comprising a clamping portion for clamping, via said closing element , said device onto said tube and a sealing portion for sealing, by said device , said end of said tube , wherein said closing element comprises a bottom part arranged for capping, in use, said tube and a wall part extending away from said bottom part , wherein said wall part encloses an angle of substantially 90 degrees with said bottom part , wherein said clamping portion comprises said wall part ; - a clamping element arranged for, in a first condition of said clamping element , transferring a clamping force onto said clamping portion of said closing element for realising, via said closing element , said clamping and arranged for, in a second condition of said clamping element , allowing said device to be removed from said tube , wherein said clamping element comprises a plurality of clamping organs arranged for said transferring, in said first condition of said clamping element , said clamping force; - an actuation element arranged for bringing said clamping element into said first condition or said second condition by actuation of said actuation element about an actuation axis (R), characterized in that , - said closing element comprises a thickened wall part at a side of said wall part facing away from said bottom part , wherein said sealing portion comprises said thickened wall part ; - said clamping element , in said first condition of said clamping element is arranged for transferring a sealing force onto said sealing portion of said closing element for realising, by said device , said sealing; and - said plurality of clamping organs are arranged for transferring said sealing force and wherein said plurality of clamping organs comprises a recess for at least partly receiving said thickened wall part . - a closing element arranged for being in contact with an outer surface of said tube , said closing element comprising a clamping portion for clamping, via said closing element , said device onto said tube and a sealing portion for sealing, by said device , said end of said tube , wherein said closing element comprises a bottom part arranged for capping, in use, said tube and a wall part extending away from said bottom part , wherein said wall part encloses an angle of substantially 90 degrees with said bottom part , wherein said clamping portion comprises said wall part ; - a clamping element arranged for, in a first condition of said clamping element , transferring a clamping force onto said clamping portion of said closing element for realising, via said closing element , said clamping and arranged for, in a second condition of said clamping element , allowing said device to be removed from said tube , wherein said clamping element comprises a plurality of clamping organs arranged for said transferring, in said first condition of said clamping element , said clamping force; - an actuation element arranged for bringing said clamping element into said first condition or said second condition by actuation of said actuation element about an actuation axis (R), - said closing element comprises a thickened wall part at a side of said wall part facing away from said bottom part , wherein said sealing portion comprises said thickened wall part ; - said clamping element , in said first condition of said clamping element is arranged for transferring a sealing force onto said sealing portion of said closing element for realising, by said device , said sealing; and - said plurality of clamping organs are arranged for transferring said sealing force and wherein said plurality of clamping organs comprises a recess for at least partly receiving said thickened wall part . <EOS>