Carrying device for musical instruments

A device for adjusting the length of a cord comprising a first part formed in a cup-shaped manner and a second part formed as an insert, wherein the the first and second parts can be pushed into each other and a spring is arranged between the the first and second parts,

• wherein the cup-shaped first part has, in a circumferential edge, a recess or entrance opening for the purpose of guiding through two cord pieces or two straps and at least two further openings in the circumferential edge for two further cord pieces or two further straps, wherein the first of the at least two further openings is arranged adjacent to the recess or entrance opening and the second of the at least two further openings is arranged opposite the first said further opening in the circumferential edge,
• wherein the insert has a middle part, a circumferential edge, and a groove with a U-turn formed by the circumferential edge and the middle part, and the circumferential edge has a recess leading into the groove, and the insert comprises at least one channel for receiving one cord piece or one strap each such channel, wherein the at least one channel has in each case elements for deflecting and for inhibiting the movement of the cord or the strap and the at least one channel is completely separated from the groove with the U-turn.