BKR6EKU Spark Plug | NGK 6993 Premium NGK spark plugs are known for their reliable performance and superior anti-fouling characteristics. NGK spark plug BKR6EKU Stock number 6993 14mm x 1.25mm thread 19.0mm thread length Gasket seat Resistor type Standard type Gap 0.024 in. (0.6mm) 5/8 in. or 16mm hex