Exothermic sleeves Volumix FX manufactured by Jodovit® are made of a highly exothermic and fire-resistant material. This ensures effective feeding of alloys (even those characterized by a narrow range of solidification temperature). These can be used with standard and alloy cast steels, grey, ductile and allow cast irons as well as copper alloys. Delivery of extra heat by the cleading during solidification of the top nob ensures significant enlargement of the module in relation to the geometric module.