A distribution transformer (15;50) comprising: a ferromagnetic core comprising at least one limb (38,40,42) extending between the first and second yokes; at least one coil assembly mounted to the at least one limb (38,40,42); a frame (17;55) for holding the core, the frame (17;55) comprising: a first clamp (10;54) comprising a pair of first plates (12;52) between which the first yoke is disposed, each of the first plates (12;52) having opposing end portions, each of which has a slot (34;64) formed therein; a second clamp (24;62) comprising a pair of second plates (14;58) between which the second yoke is disposed, each of the second plates (14;58) having opposing end portions, each of which has a slot (34;64) formed therein; first (20;51) and second (26;53) side supports, each of which has opposing side edges and opposing first and second end portions, characterized in that: the first end portion of the first (20;51) and second (26;53) side supports have first tabs (18;72) extending outwardly from the side edges respectively, and the second end portion of the first (20;51) and second (26;53) side supports have second tabs (28;74) extending outwardly from the side edges, respectively; and wherein the first tabs (18;72) of the first (20;51) and second (26;53) side supports are disposed in the slots (34;64) of the first plates (12;52) of the first clamp, respectively, and the second tabs (28;74) of the first (20;51) and second (26;53) side supports are disposed in the slots (34;64) of the second plates (14;58) of the second clamp (24;62), respectively. a ferromagnetic core comprising at least one limb (38,40,42) extending between the first and second yokes; at least one coil assembly mounted to the at least one limb (38,40,42); a frame (17;55) for holding the core, the frame (17;55) comprising: a first clamp (10;54) comprising a pair of first plates (12;52) between which the first yoke is disposed, each of the first plates (12;52) having opposing end portions, each of which has a slot (34;64) formed therein; a second clamp (24;62) comprising a pair of second plates (14;58) between which the second yoke is disposed, each of the second plates (14;58) having opposing end portions, each of which has a slot (34;64) formed therein; first (20;51) and second (26;53) side supports, each of which has opposing side edges and opposing first and second end portions, a first clamp (10;54) comprising a pair of first plates (12;52) between which the first yoke is disposed, each of the first plates (12;52) having opposing end portions, each of which has a slot (34;64) formed therein; a second clamp (24;62) comprising a pair of second plates (14;58) between which the second yoke is disposed, each of the second plates (14;58) having opposing end portions, each of which has a slot (34;64) formed therein; first (20;51) and second (26;53) side supports, each of which has opposing side edges and opposing first and second end portions, characterized in that: the first end portion of the first (20;51) and second (26;53) side supports have first tabs (18;72) extending outwardly from the side edges respectively, and the second end portion of the first (20;51) and second (26;53) side supports have second tabs (28;74) extending outwardly from the side edges, respectively; and wherein the first tabs (18;72) of the first (20;51) and second (26;53) side supports are disposed in the slots (34;64) of the first plates (12;52) of the first clamp, respectively, and the second tabs (28;74) of the first (20;51) and second (26;53) side supports are disposed in the slots (34;64) of the second plates (14;58) of the second clamp (24;62), respectively. the first end portion of the first (20;51) and second (26;53) side supports have first tabs (18;72) extending outwardly from the side edges respectively, and the second end portion of the first (20;51) and second (26;53) side supports have second tabs (28;74) extending outwardly from the side edges, respectively; and wherein the first tabs (18;72) of the first (20;51) and second (26;53) side supports are disposed in the slots (34;64) of the first plates (12;52) of the first clamp, respectively, and the second tabs (28;74) of the first (20;51) and second (26;53) side supports are disposed in the slots (34;64) of the second plates (14;58) of the second clamp (24;62), respectively.