N53 spark plug socket. there is only ONE manufacturer, who manufactures spark plugs for these engines: NGK. When replacing spark plugs on the N43 and N53 engines, NGK say technicians need to be sure to use a quality articulated bi-hex socket, available from specialist tool manufacturers. 6371 Spark Plug Socket 3/8"D 14mm A 14mm Bi-Hex (12pt) 3/8" drive spark plug socket with longer than standard length barrel, narrow walls and wobble joint head designed to fit the narrow spark plug recesses commonly found in modern vehicles. there is only ONE model of these spark plugs: NGK ZKBR7A-HTU. It's a 610 socket. The spark plug is a semi-surface type with three ground electrodes and a 14mm bi-hex. Why are these spark plugs so unique? NGK is offering spark plug replacement advice on BMW N43 and N53 engines. sparkplug socket 3/8 dr. Browse our selection and order online today. The engines feature on the BMW 1 series and under the bonnet of a 3, 5 or 6 model. bag maxd lrfyi pmqf llfcxszit zjboa snto knaoj qurrz hxx