A fixing device for fixing two beam profiles (3,4) comprising recessed channels, the fixing device comprising: a first plate element comprising a contact side configured to abut a contact side (16,17) of a second and a third plate element (13,14), the first plate element further comprising two lug portions and a clamping portion, each lug portion comprising a protrusion protruding in a direction away from the contact side and configured to be inserted into a respective recessed channel, characterised in that the fixing device further comprises: the second and third plate element (13,14), each further comprising a lug portion (24,24') and a clamping portion (27,27'), the lug portion (24,24') comprising a protrusion (25,25') protruding in a direction away from the contact side (13,14) and configured to be inserted into a respective recessed channel, the contact side (16,17) of the second and the third plate element (13,14) being configured to pivotably abut the contact side of the first plate element between the lug portion (18, 24, 24') and the respective clamping portion (22, 27, 27'), clamping means configured to bias the clamping portion of the first plate element in a direction towards the clamping portion (27,27') of the second and third plate element (13,14) such that the second and third plate element (13,14) pivot relative to the first plate element, and the lug portion (24,24') of the second and third plate element (13,14) is biased in a direction away from the lug portions of the first plate element into abutment with the respective recessed channels of the beam profiles (3,4). a first plate element comprising a contact side configured to abut a contact side (16,17) of a second and a third plate element (13,14), the first plate element further comprising two lug portions and a clamping portion, each lug portion comprising a protrusion protruding in a direction away from the contact side and configured to be inserted into a respective recessed channel, characterised in that the fixing device further comprises: the second and third plate element (13,14), each further comprising a lug portion (24,24') and a clamping portion (27,27'), the lug portion (24,24') comprising a protrusion (25,25') protruding in a direction away from the contact side (13,14) and configured to be inserted into a respective recessed channel, the contact side (16,17) of the second and the third plate element (13,14) being configured to pivotably abut the contact side of the first plate element between the lug portion (18, 24, 24') and the respective clamping portion (22, 27, 27'), clamping means configured to bias the clamping portion of the first plate element in a direction towards the clamping portion (27,27') of the second and third plate element (13,14) such that the second and third plate element (13,14) pivot relative to the first plate element, and the lug portion (24,24') of the second and third plate element (13,14) is biased in a direction away from the lug portions of the first plate element into abutment with the respective recessed channels of the beam profiles (3,4). the second and third plate element (13,14), each further comprising a lug portion (24,24') and a clamping portion (27,27'), the lug portion (24,24') comprising a protrusion (25,25') protruding in a direction away from the contact side (13,14) and configured to be inserted into a respective recessed channel, the contact side (16,17) of the second and the third plate element (13,14) being configured to pivotably abut the contact side of the first plate element between the lug portion (18, 24, 24') and the respective clamping portion (22, 27, 27'), clamping means configured to bias the clamping portion of the first plate element in a direction towards the clamping portion (27,27') of the second and third plate element (13,14) such that the second and third plate element (13,14) pivot relative to the first plate element, and the lug portion (24,24') of the second and third plate element (13,14) is biased in a direction away from the lug portions of the first plate element into abutment with the respective recessed channels of the beam profiles (3,4).