A U-shaped tube blanket, comprising: an air input cross section for receiving heated air from a convective warmer; two legs (8, 10) each extending from a corresponding end of said cross section for sandwiching a patient therebetween, wherein said each leg (8, 10) comprises a plurality of successive sections (16a, 16b, 16c, 16a', 16b', 16c') of holes (12a, 12b, 12c, 12a', 12b' 12c') extending substantially along the length of each leg (8, 10), the holes being adapted to vent the heated air, said sections extending along each leg (8, 10) from a proximal portion (16a, 16a') of holes adjacent to said cross section to a distal section (16c, 16c') of holes away from said cross section, each of the sections (16a, 16b, 16c, 16a', 16b', 16c') having multiple holes (12a, 12b, 12c, 12a', 12b' 12c') of a given dimension, wherein the size of the holes (12a, 12b, 12c, 12a', 12b' 12c') is the same within said each section (16a, 16b, 16c, 16a', 16b', 16c') but is different from the size of the holes at the other sections, at least one middle section (16b, 16b') of holes (12b, 12b') of the same dimension between the proximal (16a, 16a') and distal (16c, 16c') sections, the dimension of the holes (12b, 12b') of the mid section (16b, 16b') being smaller than the holes (12c, 12c') of the distal section (16c, 16c') but larger than the holes (12a, 12a') of the proximal section (16a, 16a'), wherein the holes (12a, 12b, 12c; 12a', 12b' 12c') in each of the successive sections (16a, 16b, 16c; 16a', 16b', 16c') along each leg (8, 10) of the blanket have a dimension greater than the previous section so that the amount of heated air output from the distal portion (16c, 16c') is greater than the amount of heated air output from the proximal portion (16a, 16a') of the legs (8, 10) to thereby provide substantially evenly distributed warmth from the heated air for a patient placed between the two legs (8, 10); and wherein each of the legs (8, 10) comprises a strap (18, 20) having one end removable from the leg so that both straps (18, 20) for the legs (8, 10) are adaptable to be used to secure the blanket to the patient. an air input cross section for receiving heated air from a convective warmer; two legs (8, 10) each extending from a corresponding end of said cross section for sandwiching a patient therebetween, wherein said each leg (8, 10) comprises a plurality of successive sections (16a, 16b, 16c, 16a', 16b', 16c') of holes (12a, 12b, 12c, 12a', 12b' 12c') extending substantially along the length of each leg (8, 10), the holes being adapted to vent the heated air, said sections extending along each leg (8, 10) from a proximal portion (16a, 16a') of holes adjacent to said cross section to a distal section (16c, 16c') of holes away from said cross section, each of the sections (16a, 16b, 16c, 16a', 16b', 16c') having multiple holes (12a, 12b, 12c, 12a', 12b' 12c') of a given dimension, wherein the size of the holes (12a, 12b, 12c, 12a', 12b' 12c') is the same within said each section (16a, 16b, 16c, 16a', 16b', 16c') but is different from the size of the holes at the other sections, at least one middle section (16b, 16b') of holes (12b, 12b') of the same dimension between the proximal (16a, 16a') and distal (16c, 16c') sections, the dimension of the holes (12b, 12b') of the mid section (16b, 16b') being smaller than the holes (12c, 12c') of the distal section (16c, 16c') but larger than the holes (12a, 12a') of the proximal section (16a, 16a'), wherein the holes (12a, 12b, 12c; 12a', 12b' 12c') in each of the successive sections (16a, 16b, 16c; 16a', 16b', 16c') along each leg (8, 10) of the blanket have a dimension greater than the previous section so that the amount of heated air output from the distal portion (16c, 16c') is greater than the amount of heated air output from the proximal portion (16a, 16a') of the legs (8, 10) to thereby provide substantially evenly distributed warmth from the heated air for a patient placed between the two legs (8, 10); and wherein each of the legs (8, 10) comprises a strap (18, 20) having one end removable from the leg so that both straps (18, 20) for the legs (8, 10) are adaptable to be used to secure the blanket to the patient.