Set of mountable parts, comprising: - a threshold comprising an elongated threshold profile, the threshold profile comprising a clamping groove, provided parallel to the threshold profile provided at a first substantially flat side of the threshold profile which in use is a bottom side, wherein the clamping groove comprises a first receiving section and a second receiving section arranged to receive a clamping profile between the first receiving section and the second receiving section; and - a clamping profile comprising a first clamping part comprising a first clamping abutment arranged to abut the first receiving section of the threshold profile of the threshold, a second clamping part comprising a second clamping abutment arranged to abut the second receiving section of the threshold profile of the threshold; wherein a first clamping abutment comprised by the clamping profile is arranged to abut the first receiving section comprised by the threshold and a second clamping abutment comprised by the clamping profile is arranged to abut the second receiving section comprised by the threshold such that the position of the clamping profile in the threshold is fixed in a direction substantially perpendicular to the first side of the threshold, and wherein when the clamping profile is clamped in the clamping groove, the clamping groove is provided in the first side of the threshold profile, characterized in that the clamping profile comprises a groove, arranged for receiving an external profile which, in use, protrudes downward from the first side of the threshold, wherein the groove is provided in a direction which is substantially parallel to the first side of the threshold, the set further comprising the external profile (205, 207), wherein the external profile is arranged to be at least partially inserted into the groove of the clamping profile. - a threshold comprising an elongated threshold profile, the threshold profile comprising a clamping groove, provided parallel to the threshold profile provided at a first substantially flat side of the threshold profile which in use is a bottom side, wherein the clamping groove comprises a first receiving section and a second receiving section arranged to receive a clamping profile between the first receiving section and the second receiving section; and - a clamping profile comprising a first clamping part comprising a first clamping abutment arranged to abut the first receiving section of the threshold profile of the threshold, a second clamping part comprising a second clamping abutment arranged to abut the second receiving section of the threshold profile of the threshold; wherein a first clamping abutment comprised by the clamping profile is arranged to abut the first receiving section comprised by the threshold and a second clamping abutment comprised by the clamping profile is arranged to abut the second receiving section comprised by the threshold such that the position of the clamping profile in the threshold is fixed in a direction substantially perpendicular to the first side of the threshold, and wherein when the clamping profile is clamped in the clamping groove, the clamping groove is provided in the first side of the threshold profile, characterized in that the clamping profile comprises a groove, arranged for receiving an external profile which, in use, protrudes downward from the first side of the threshold, wherein the groove is provided in a direction which is substantially parallel to the first side of the threshold, the set further comprising the external profile (205, 207), wherein the external profile is arranged to be at least partially inserted into the groove of the clamping profile.