A breaking hammer comprising: a percussion device ; a tool connectable to the percussion device ; a sealing housing , which is located around the tool ; a seal , which is located in the sealing housing ; wherein the seal is a sleeve-like piece having an inner periphery, an outer periphery and an axial length; the inner periphery of the seal comprises a tool opening provided with sealing surfaces, which are intended to be arranged to face towards the tool to be sealed; and the outer periphery of the seal is provided with fastening surfaces for fastening the seal to a body of the breaking hammer ; characterized in that the seal has two-part configuration and comprises a first seal element and a second seal element which are arranged successively in axial direction; the mentioned fastening surfaces are located on the outer periphery of the first seal element ; the second seal element is fastened only to the first seal element , whereby it is without fastening surfaces for fastening it to the body of the breaking hammer ; the first seal element is made of resilient material and comprises a first tool opening which is intended to be in resilient contacting relationship with the tool ; the second seal element is a rigid element and comprises a second tool opening , which is dimensioned to form a sealing clearance between the tool and the second seal element ; diameter (D1) of the first tool opening is smaller than diameter (D2) of the second tool opening ; and the resilient first seal element of the seal allows the rigid second seal element to move transversally (T) together with the tool relative to the sealing housing . a percussion device ; a tool connectable to the percussion device ; a sealing housing , which is located around the tool ; a seal , which is located in the sealing housing ; wherein the seal is a sleeve-like piece having an inner periphery, an outer periphery and an axial length; the inner periphery of the seal comprises a tool opening provided with sealing surfaces, which are intended to be arranged to face towards the tool to be sealed; and the outer periphery of the seal is provided with fastening surfaces for fastening the seal to a body of the breaking hammer ; characterized in that the seal has two-part configuration and comprises a first seal element and a second seal element which are arranged successively in axial direction; the mentioned fastening surfaces are located on the outer periphery of the first seal element ; the second seal element is fastened only to the first seal element , whereby it is without fastening surfaces for fastening it to the body of the breaking hammer ; the first seal element is made of resilient material and comprises a first tool opening which is intended to be in resilient contacting relationship with the tool ; the second seal element is a rigid element and comprises a second tool opening , which is dimensioned to form a sealing clearance between the tool and the second seal element ; diameter (D1) of the first tool opening is smaller than diameter (D2) of the second tool opening ; and the resilient first seal element of the seal allows the rigid second seal element to move transversally (T) together with the tool relative to the sealing housing . <EOS>