Feature: 1. [APPLICABLE MODEL] This extruder heater block kit is compatible with FDM 3D printers and is suitable for Ender 3 S1 3D printers with stable performance. 2. [UPGRADING KIT] The 24V heating rod in the kit measures 6 x 20mm and is equipped with an NTC100K B3950 thermistor and measures 3 x 5.5mm. 3. [METAL MATERIAL] The heating block is made of aluminum, the thermal insulation is made of stainless steel, and all parts are machined with high accuracy. 4. [COMPLETE ACCESSORIES] The kit includes a heater, a thermistor, a heating block, a silicone sleeve, a nozzle, a heating cloth with PTFE tube and 2PCS screws. 5. [THERMISTOR] The thermistor provided in this kit is the same as the normal NTC100K 3950B thermistor, you should choose number 1 in the for Marlin firmware. Specification: Item Type: Extruder Heater Block Kit Material: Aluminum alloy, stainless steel, silicone, nickel plated copper Heating Rod: 24V 40W Throat Material: Stainless steel Features: High temperature printing below 260 °C, titanium alloy material upward can reduce heat conduction. Nozzle Diameter: 0.4mm Applicable Models: Ender 3 S1 printer Heating Rod Size: Dia 6 x 20mm / 0.2 x 0.8in Total Length with Terminal: 73mm / 2.9in Thermistor Rod Size: 3 x 5.5mm / 0.1 x 0.22in. Package List: 1 x Extruder Heater Block Kit