1. FOR KARCHER COMPATIBILITY: This safety lock with black Oring 4.590105.0 is specifically designed for several Karcher steam cleaner models including SC1.010, SC1.020, SC1.030, SC2.000, SC3.000 and many more, providing a precise fit that helps maintain the performance of your steam cleaning. 2. ENHANCED SAFETY FEATURES: With a quality safety valve combined with a sturdy black Oring 6.363279.0, this replacement part creates a reliable seal that effectively reduces the risk of leaks and allows safe operation throughout your cleaning session. 3. CONSTRUCTION: Made of quality materials, this safety lock is built to withstand temperature steam cleanings and regular use, providing longlasting reliability without compromising performance even after extended cleaning tasks. 4. EASY REPLACEMENT PROCESS: Thoughtful design allows for quick and straightforward installation with no special tools—simply remove the old cap and attach this replacement part to get back to your cleaning routine in minutes.