Exotec exothermic sleeves are used by all steel foundries and many grey iron foundries to improve their yield and productivity.They also reduce fetling costs. Technical specifications: 1)modulus extension factor : 1.80 upto 6" diameter x 6" height. 2)feeding efficiency : 34% on cubes and upto 65% on plates. 3)available in cylindrical, spherical and elliptical shapes.