A method of providing an insertion guidance tip at a distal end of an interdental brush, the method comprising: positioning a plurality of filaments (10, 20) side by side along a brush portion extending along a longitudinal direction between two strands (3a, 3b) of a core member, the two strands (3a, 3b) of the core member extending alongside each other along the longitudinal direction and being formed by folding the core member, wherein there is made use of two different set of filaments (10; 20) to provide a transition in perceived properties close to the distal end, wherein said act of positioning comprises: positioning a first set of filaments side by side along a first longitudinal sub-length of the brush portion, the filaments of the first set of filaments having a first filament diameter, and positioning a second set of filaments along a second longitudinal sub-length of the brush portion, the filaments of the second set of filaments having a second filament diameter, wherein the second filament diameter is smaller than the first filament diameter in that the second filament diameter is between 60-95% of the first filament diameter, wherein the second longitudinal sub-length is positioned at the distal end of the interdental brush, wherein the second sub-length has a length along the longitudinal direction that is less than 15% of a longitudinal extension of the brush portion, and wherein the second sub-length has a length extending along less than three twists of the core member, whereby the transition in perceived properties formed by the use of the two different sets of filaments (10, 20) is provided close to the distal end, and the method further comprising: twisting the two strands (3a, 3b) about an axis along the longitudinal direction to form a twisted core member and to thereby fasten the filaments (10, 20) of the first and second set of filaments between the two strands (3a, 3b) such that the filaments (10, 20) of the first and second set of filaments extend radially from the twisted core member and become arranged side by side along a helix extending along the longitudinal direction. positioning a plurality of filaments (10, 20) side by side along a brush portion extending along a longitudinal direction between two strands (3a, 3b) of a core member, the two strands (3a, 3b) of the core member extending alongside each other along the longitudinal direction and being formed by folding the core member, wherein there is made use of two different set of filaments (10; 20) to provide a transition in perceived properties close to the distal end, wherein said act of positioning comprises: positioning a first set of filaments side by side along a first longitudinal sub-length of the brush portion, the filaments of the first set of filaments having a first filament diameter, and positioning a second set of filaments along a second longitudinal sub-length of the brush portion, the filaments of the second set of filaments having a second filament diameter, wherein the second filament diameter is smaller than the first filament diameter in that the second filament diameter is between 60-95% of the first filament diameter, wherein the second longitudinal sub-length is positioned at the distal end of the interdental brush, wherein the second sub-length has a length along the longitudinal direction that is less than 15% of a longitudinal extension of the brush portion, and wherein the second sub-length has a length extending along less than three twists of the core member, whereby the transition in perceived properties formed by the use of the two different sets of filaments (10, 20) is provided close to the distal end, and positioning a first set of filaments side by side along a first longitudinal sub-length of the brush portion, the filaments of the first set of filaments having a first filament diameter, and positioning a second set of filaments along a second longitudinal sub-length of the brush portion, the filaments of the second set of filaments having a second filament diameter, wherein the second filament diameter is smaller than the first filament diameter in that the second filament diameter is between 60-95% of the first filament diameter, wherein the second longitudinal sub-length is positioned at the distal end of the interdental brush, wherein the second sub-length has a length along the longitudinal direction that is less than 15% of a longitudinal extension of the brush portion, and wherein the second sub-length has a length extending along less than three twists of the core member, the method further comprising: twisting the two strands (3a, 3b) about an axis along the longitudinal direction to form a twisted core member and to thereby fasten the filaments (10, 20) of the first and second set of filaments between the two strands (3a, 3b) such that the filaments (10, 20) of the first and second set of filaments extend radially from the twisted core member and become arranged side by side along a helix extending along the longitudinal direction.