An indexable reversible cutting insert (20, 130) having an insert axis (B2, B3), and comprising: a polygonal shaped first end surface (22, 132) defining a first end plane (P1, S1) and a polygonal shaped second end surface (24, 134) defining a second end plane (P2, S2), the first and second end planes (P1, S1, P2, S2) being parallel to one another; a peripheral side surface (26, 136) extending between the end surfaces (22, 24, 132, 134), the peripheral side surface (26, 136) including first peripheral side portions (30, 140) alternated in the circumferential direction with second peripheral side portions (32, 142); a first edge (46, 135) formed along the intersection of the first end surface (22, 132) with the peripheral side surface (26, 136), the first edge comprising a plurality of first cutting edges (58, 161) alternated with a plurality of second cutting edges (60, 163); a second edge (48, 137) formed along the intersection of the second end surface (24, 134) with the peripheral side surface (26, 136), the second edge comprising a plurality of first cutting edges (52, 165) alternated with a plurality of second cutting edges (74, 167); wherein each of the first peripheral side portions (30, 140) comprises a first sub-face (70, 160) which forms a first insert internal angle (α, φ) with the first end plane (P1, S1) and a second sub-face (72, 162) which forms an acute second insert internal angle (θ, ψ) with the second end plane (P2, S2), the first sub-face and the second sub-face of each first peripheral side portion (30, 140) intersecting at a first line which is a first distance (d1, d) from the first end plane (P1, S1) and a second distance (d2, d) from the second end plane (P2, S2); characterised in that each of the second peripheral side portions (32, 142) comprises a first sub-face (66, 156) which forms a first insert internal angle (α, φ) with the second end plane (P2, S2) and a second sub-face (68, 158) which forms an acute second insert internal angle (θ, ψ) with the first end plane (P1, S1), the first sub-face and the second sub-face of each second peripheral side portion (32, 142) intersecting at a second line which is a first distance (d1, d) from the second end plane (P2, S2) and a second distance (d2, d) from the first end plane (P1, S1). a polygonal shaped first end surface (22, 132) defining a first end plane (P1, S1) and a polygonal shaped second end surface (24, 134) defining a second end plane (P2, S2), the first and second end planes (P1, S1, P2, S2) being parallel to one another; a peripheral side surface (26, 136) extending between the end surfaces (22, 24, 132, 134), the peripheral side surface (26, 136) including first peripheral side portions (30, 140) alternated in the circumferential direction with second peripheral side portions (32, 142); a first edge (46, 135) formed along the intersection of the first end surface (22, 132) with the peripheral side surface (26, 136), the first edge comprising a plurality of first cutting edges (58, 161) alternated with a plurality of second cutting edges (60, 163); a second edge (48, 137) formed along the intersection of the second end surface (24, 134) with the peripheral side surface (26, 136), the second edge comprising a plurality of first cutting edges (52, 165) alternated with a plurality of second cutting edges (74, 167); wherein each of the first peripheral side portions (30, 140) comprises a first sub-face (70, 160) which forms a first insert internal angle (α, φ) with the first end plane (P1, S1) and a second sub-face (72, 162) which forms an acute second insert internal angle (θ, ψ) with the second end plane (P2, S2), the first sub-face and the second sub-face of each first peripheral side portion (30, 140) intersecting at a first line which is a first distance (d1, d) from the first end plane (P1, S1) and a second distance (d2, d) from the second end plane (P2, S2); characterised in that each of the second peripheral side portions (32, 142) comprises a first sub-face (66, 156) which forms a first insert internal angle (α, φ) with the second end plane (P2, S2) and a second sub-face (68, 158) which forms an acute second insert internal angle (θ, ψ) with the first end plane (P1, S1), the first sub-face and the second sub-face of each second peripheral side portion (32, 142) intersecting at a second line which is a first distance (d1, d) from the second end plane (P2, S2) and a second distance (d2, d) from the first end plane (P1, S1).