Compatible with Prusa MK4 only (not for Prusa XL). Includes full hotend replacement kit: - Aluminum heating block - 24V 40W heater - Thermistor (104NT-4-R025H42G, 300��C max) - Silicone sleeve - 0.4mm brass nozzle Modular design simplifies nozzle replacement. Aluminum alloy construction ensures durability. Note: No installation guide included (professional installation recommended). Minor variations may occur between batches. Colors may slightly differ due to lighting/monitor settings. Package contents listed above only. Verify compatibility before purchase. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-YJL official store