Clamp with recess having a guiding groove

A band clamp, comprising:

• a clamping band (10) having two end portions (11, 12) which overlap one another in a closed condition of the band clamp, the clamping band (10) comprising a tongue (13) arranged at an overlapped inner band portion (11), and a tongue recess (14) provided in an inner side of an overlapping outer band portion (12) and being complementary to a shape of the tongue (13) for receiving the tongue (13), wherein the tongue recess (14) includes two opposing side faces (14d, 14e) connected by a closed roof surface (14f), wherein the roof surface (14f) of the tongue recess (14) includes a longitudinal groove (20) and a tip portion of the tongue (13) includes a protrusion (21) configured to engage in the groove (20), wherein an entry of the tongue recess (14) is formed between transversal steps (14a, 14b) formed in the clamping band (14), wherein the groove (20) extends outside the tongue recess (14) into an inner surface (12a) of the outer band portion (12) beyond the transversal steps (14a, 14b).