Locking element for locking a sealing membrane for a pool, the pool comprising a vertical wall, extending between a bottom of the pool and a coping, the vertical wall being provided with a support comprising a groove, the groove being intended to receive an edge of the sealing membrane, the locking element being intended to lock the edge of the sealing membrane in the groove, the locking element comprising: • a tongue, extending between a distal end (12 d) and a proximal end (12 p), in an extension direction, the distal end being intended to be introduced into the groove so as to block the membrane edge engaged in the groove by exerting a pressure; • a strip, connected to the proximal end (12 p) of the tongue, and extending perpendicularly or substantially perpendicularly to the extension direction, so as to extend against the vertical wall of the pool when the tongue is introduced into the groove; • the strip extending on either side of the proximal end (12 p) of the tongue, between an upper edge (11 sup) and a lower edge (11 inf), the distance between the upper edge and the lower edge forming a width of the strip, which is greater than 1 cm, so as to mask the support; the locking element being such that: • the strip delimits a rear space (11 AR), comprising the distal end (12 d) of the tongue, and a front space (11 AV), not comprising the distal end of the tongue; • the strip has an upper part (11 1), extending between the proximal end of the tongue (12 p) and the upper edge (11 SuP); • the upper part (11 1) of the strip is curved towards the front space (11 AV); the locking element being characterized in that: • the distance between the proximal end (12 p) and the upper edge (11 sup) is greater than 1 cm; • the locking element is monolithic, the strip and the tongue being formed from the same flexible material. • a tongue, extending between a distal end (12 d) and a proximal end (12 p), in an extension direction, the distal end being intended to be introduced into the groove so as to block the membrane edge engaged in the groove by exerting a pressure; • a strip, connected to the proximal end (12 p) of the tongue, and extending perpendicularly or substantially perpendicularly to the extension direction, so as to extend against the vertical wall of the pool when the tongue is introduced into the groove; • the strip extending on either side of the proximal end (12 p) of the tongue, between an upper edge (11 sup) and a lower edge (11 inf), the distance between the upper edge and the lower edge forming a width of the strip, which is greater than 1 cm, so as to mask the support; the locking element being such that: • the strip delimits a rear space (11 AR), comprising the distal end (12 d) of the tongue, and a front space (11 AV), not comprising the distal end of the tongue; • the strip has an upper part (11 1), extending between the proximal end of the tongue (12 p) and the upper edge (11 SuP); • the upper part (11 1) of the strip is curved towards the front space (11 AV); • the strip delimits a rear space (11 AR), comprising the distal end (12 d) of the tongue, and a front space (11 AV), not comprising the distal end of the tongue; • the strip has an upper part (11 1), extending between the proximal end of the tongue (12 p) and the upper edge (11 SuP); • the upper part (11 1) of the strip is curved towards the front space (11 AV); the locking element being characterized in that: • the distance between the proximal end (12 p) and the upper edge (11 sup) is greater than 1 cm; • the locking element is monolithic, the strip and the tongue being formed from the same flexible material. • the distance between the proximal end (12 p) and the upper edge (11 sup) is greater than 1 cm; • the locking element is monolithic, the strip and the tongue being formed from the same flexible material.