A clamping collar (100; 200; 300) comprising a strap (120; 220; 320) of elongate shape and a head (110; 210; 310) from which the strap (120; 220; 320) extends until it reaches a free end (121; 221; 321), the head (110; 210; 310) including an opening (114; 214; 314) through which the strap (120; 220; 320) is adapted to be inserted, the strap (120; 220; 320) comprising: · at least one portion in relief (124; 224; 324) projecting from one of the faces (122, 123; 222, 223; 322, 323) of the strap (120; 220; 320), in the proximity of its free end (121; 221; 321); · at least one first group of teeth (125; 225; 325) projecting from one of the faces (122, 123; 222, 223; 322, 323) of the strap (120; 220; 320), each of said teeth (125; 225; 325) being adapted to be held by co-operating with a catch tooth (115; 215; 315) of said head (110; 210; 310) when the strap (120; 220; 320) is inserted into the opening (114; 214; 314) of the head, each tooth (125; 225; 325) of said first group of teeth presenting a profile that includes at least one sharp edge and presenting a first height (H21; H22; H23), causing it to co-operate in non-releasable manner with said catch tooth (115; 215; 315); and · a second group of teeth (126; 226; 326) projecting from one of the faces (122, 123; 222, 223; 322, 323) of the strap (120; 220; 320), each of said teeth (126; 226; 326) presenting a profile that includes at least one sharp edge and presenting a second height (H31; H32; H33) that is greater than said first height (H21; H22; H23), causing it to co-operate in non-releasable manner with said catch tooth (115; 215; 315) when the strap (120; 220; 320) is inserted into the opening (114; 214; 314) of said head; each of the first and second heights being defined as the distance between a reference plane (P1; P2; P3) and the tip of the tooth that is the furthest away from the reference plane (P1; P2; P3); said clamping collar being characterized in that: · said portion in relief (124; 224; 324) is adapted to be held by co-operating with a catch tooth (115; 215; 315) of said head (110; 210; 310) when the strap (120; 220; 320) is inserted into the opening (114; 214; 314) of the head (110; 210; 310), and presents a profile free from any sharp edge, allowing it to co-operate in releasable manner with said catch tooth (115; 215; 315); and · said second group of teeth (126; 226; 326) extends between the first group of teeth (125; 225; 325) and said head (110; 210; 310). · at least one portion in relief (124; 224; 324) projecting from one of the faces (122, 123; 222, 223; 322, 323) of the strap (120; 220; 320), in the proximity of its free end (121; 221; 321); · at least one first group of teeth (125; 225; 325) projecting from one of the faces (122, 123; 222, 223; 322, 323) of the strap (120; 220; 320), each of said teeth (125; 225; 325) being adapted to be held by co-operating with a catch tooth (115; 215; 315) of said head (110; 210; 310) when the strap (120; 220; 320) is inserted into the opening (114; 214; 314) of the head, each tooth (125; 225; 325) of said first group of teeth presenting a profile that includes at least one sharp edge and presenting a first height (H21; H22; H23), causing it to co-operate in non-releasable manner with said catch tooth (115; 215; 315); and · a second group of teeth (126; 226; 326) projecting from one of the faces (122, 123; 222, 223; 322, 323) of the strap (120; 220; 320), each of said teeth (126; 226; 326) presenting a profile that includes at least one sharp edge and presenting a second height (H31; H32; H33) that is greater than said first height (H21; H22; H23), causing it to co-operate in non-releasable manner with said catch tooth (115; 215; 315) when the strap (120; 220; 320) is inserted into the opening (114; 214; 314) of said head; · said portion in relief (124; 224; 324) is adapted to be held by co-operating with a catch tooth (115; 215; 315) of said head (110; 210; 310) when the strap (120; 220; 320) is inserted into the opening (114; 214; 314) of the head (110; 210; 310), and presents a profile free from any sharp edge, allowing it to co-operate in releasable manner with said catch tooth (115; 215; 315); and · said second group of teeth (126; 226; 326) extends between the first group of teeth (125; 225; 325) and said head (110; 210; 310).