A fuse load break switch for fastening to busbars of one or more different widths, wherein the fuse load break switch comprises a base element, a cover element, a hook part, a latching device and a first spring element, wherein the latching device comprises a clamping portion for clamping or gripping a busbar between the clamping portion and the hook part, and a locking portion for detachably locking the latching device on the base element in a locking position, wherein the cover element is arranged movably back and forth relative to the base element between an open position and a closed operating position, wherein the latching device is arranged movably back and forth relative to the base element between the locking position, for arranging the fuse load break switch relative to a busbar so that the busbar can be positioned between the clamping portion and the hook part, and one or more clamping positions, for clamping or gripping the busbar between the clamping portion and the hook part, wherein the first spring element is designed such that it preloads the latching device in the direction of the hook part in every position, characterised in that the fuse load break switch is designed such that locking of the latching device in the locking position is prevented and/or released when the cover element is in its closed operating position or is brought into the closed operating position, wherein the locking portion comprises a hook element, wherein, when the latching device is in the locking position, the hook element is arranged movably back and forth relative to the base element between a hook element locking position for locking the latching device on the base element and a release position for releasing the locking, wherein the hook element comprises an inclination face, which is designed such that, when the cover element is brought into the closed operating position, the cover element contacts the inclination face and/or exerts a force on the inclination face so that the hook element is moved from the hook element locking position to the release position counter to the second spring force. wherein the fuse load break switch comprises a base element, a cover element, a hook part, a latching device and a first spring element, wherein the latching device comprises a clamping portion for clamping or gripping a busbar between the clamping portion and the hook part, and a locking portion for detachably locking the latching device on the base element in a locking position, wherein the cover element is arranged movably back and forth relative to the base element between an open position and a closed operating position, wherein the latching device is arranged movably back and forth relative to the base element between the locking position, for arranging the fuse load break switch relative to a busbar so that the busbar can be positioned between the clamping portion and the hook part, and one or more clamping positions, for clamping or gripping the busbar between the clamping portion and the hook part, wherein the first spring element is designed such that it preloads the latching device in the direction of the hook part in every position, characterised in that the fuse load break switch is designed such that locking of the latching device in the locking position is prevented and/or released when the cover element is in its closed operating position or is brought into the closed operating position, wherein the locking portion comprises a hook element, wherein, when the latching device is in the locking position, the hook element is arranged movably back and forth relative to the base element between a hook element locking position for locking the latching device on the base element and a release position for releasing the locking, wherein the hook element comprises an inclination face, which is designed such that, when the cover element is brought into the closed operating position, the cover element contacts the inclination face and/or exerts a force on the inclination face so that the hook element is moved from the hook element locking position to the release position counter to the second spring force.