Review on NGK 54181 EUC051 Spark Plug by Ryan Frawley

01/09/2015: I am upgrading the ignition system on my 20 year old E420. The Mercedes tech recommended OEM connector cables, but if I'm looking to save some money an NKG set would probably be fine. Revain had a $159 set with free shipping, I got the last one and they are now selling for $233 which is still a good price. Replacement parts arrived today, very high quality and high quality. The NGK package was a bit shabby but it's ok. The packaging clearly says "Made in the USA". "NGK Copper Spark Plug Cable Silicone USA" is written on the blue wires. Spark plug boots are made of black rubber and stainless steel. The black rubber ends are marked "Beru W-Germany". Beru cable sets are recommended on several Mercedes forums, so I'm very happy with their cost many times cheaper than at the dealer. Don (Ollo)