A self-crimped multi-component fiber, comprising: (i) a first component comprising a first polymeric material, wherein the first polymeric material comprises a first melt flow rate less than 50 g/10 min, such as at most any of the following: 48, 46, 44, 42, 40, 38, 36, 35, 34, 32, and 30 g/10 min and/or at least any of the following: 20, 22, 24, 25, 26, 28, 30, 32, 34, and 35 g/10 min; wherein the first polymeric material comprises a first polyolefin composition, which comprises a blend of a polyolefin fraction A and a polyolefin fraction B; wherein the polyolefin fraction A accounts for more than 50% by weight of the first polyolefin composition; wherein the first polyolefin composition has a polyolefin fraction A-MFR being less than a polyolefin fraction B-MFR of the polyolefin fraction B, wherein a MFR-ratio between the polyolefin fraction B-MFR and the polyolefin fraction A-MFR is from 15:1 to 100:1; wherein the first polyolefin composition comprises from 0.5 % by weight to 12 % by weight of the first polyolefin fraction B; (ii) a second component comprising a second polymeric material, wherein the second polymeric material comprises a second polyolefin composition, wherein the second component is different than the first component; wherein the SMF comprises one or more three-dimensional crimped portions; and wherein optionally the second polymeric material comprises a second MFR less than 50 g/10 min, such as at most any of the following: 48, 46, 45, 42, 40, 38, 36, 35, 34, 32, and 30 g/10 min and/or at least any of the following: 20, 22, 24, 25, 26, 28, 30, 32, 34, and 35 g/10 min; wherein the MFR is determined in accordance with ASTM-D1238 (2.16 kg at 230 °C). (i) a first component comprising a first polymeric material, wherein the first polymeric material comprises a first melt flow rate less than 50 g/10 min, such as at most any of the following: 48, 46, 44, 42, 40, 38, 36, 35, 34, 32, and 30 g/10 min and/or at least any of the following: 20, 22, 24, 25, 26, 28, 30, 32, 34, and 35 g/10 min; wherein the first polymeric material comprises a first polyolefin composition, which comprises a blend of a polyolefin fraction A and a polyolefin fraction B; wherein the polyolefin fraction A accounts for more than 50% by weight of the first polyolefin composition; wherein the first polyolefin composition has a polyolefin fraction A-MFR being less than a polyolefin fraction B-MFR of the polyolefin fraction B, wherein a MFR-ratio between the polyolefin fraction B-MFR and the polyolefin fraction A-MFR is from 15:1 to 100:1; wherein the first polyolefin composition comprises from 0.5 % by weight to 12 % by weight of the first polyolefin fraction B; (ii) a second component comprising a second polymeric material, wherein the second polymeric material comprises a second polyolefin composition, wherein the second component is different than the first component; wherein the SMF comprises one or more three-dimensional crimped portions; and wherein optionally the second polymeric material comprises a second MFR less than 50 g/10 min, such as at most any of the following: 48, 46, 45, 42, 40, 38, 36, 35, 34, 32, and 30 g/10 min and/or at least any of the following: 20, 22, 24, 25, 26, 28, 30, 32, 34, and 35 g/10 min; wherein the MFR is determined in accordance with ASTM-D1238 (2.16 kg at 230 °C).