Marathon Heater [India] Pvt. Ltd. Offers Cartridge Heater with Stainless Steel Tubing. Marathon Heater [India] Pvt. Ltd. Manufactures Temperature Sensors, High Quality Heaters etc. The Cartridge Heater with Stainless Steel Tubing has specially designed cores, careful selection of magnesium oxide fill, nickel chromium resistance wire, stainless steel tubing, and carefully controlled production processes etc. The Cartridge Heater with Stainless Steel Tubing has high impact ceramic cap retards contamination and is suitable for high vibration applications. Deep holes in cap prevent fraying of leads when bent.