This is for a rare BERU glow plug tester made in West Germany specifically for diesels of the era and will work on any 11 volt glow plug. This tool enables you to test your glow plugs instantly and accurately without having to remove them from the engine. BERU never marketed these outside of Europe so the markings on this are all in German. A translation is included. After you test the first glow plug you will know the tool. One of the standard methods to test your glow plugs is to remove each one of them. It is tedious and the down-time always runs longer just to get poor information. Each plug is often tested directly off of the battery(flawed test at full 12V) and then the brightness of the glow is observed. This is pointless. If one plug is glowing at 1000'F and the other 4 are brighter at 1300'F then they're all bad because good plugs glow at around 1650'F. Another option is checking resistance or replace all of the glow plugs outright(max labor and parts) but if the problem is just one plug then replacing all of them is excessive. The easiest by far is to remove the wire from a glow plug, connect this tester and press the button. This tester is a major time saver plus the feedback is accurate. Never pull a glow plug unless you already know it's bad. This tester also bypasses the vehicles' glow plug system and runs the entire test through the device so you're not turning the key every time. This tool will also tell you if a glow plug is bad due to a direct short by blowing its onboard fuse. This takes a standard Euro type 16A protection fuse inside the unit just like a multimeter. If all of the plugs test good then the glow plug relay or the wiring is suspect. Markings on front: Gut = Good Defekt = Defective testbereift = Ready for test Test lauft = Test is running Schnelltester = Quicktester fur 11 volt = For 11 volt stabgluhkerzen pin glow plugs ***As per the tool this is for glow plugs that run at 11 volts which in the world of glow plugs classifies them as "high voltage." Most other glow plugs are run at 6 volts or less which will not hold up to this 11 volt plug tester. Free shipping in the U.S. If there's a problem let me know and I'll work with you. My work keeps me away often so to be safe, handling time to get this shipped out is 1 week. SHIPPING ADDRESS: I can only send your item to the registered shipping address at time of payment.