This kit replaces crack-prone plastic pieces with alloy versions for a replace-and-forget upgrade. Kit includes AJ8-2217 thermostat housing in alloy, JA-AJ8-5875 thermostat cover in alloy, JA-NCA2246BA O-ring, JA-NCA2269CA O-ring and JA-NCA2270AC screw cap in alloy. Does not include a new thermostat. (Accepts standard thermostat.) This kit fits non-supercharged "Series I" XJ8 1997-2002 and non-supercharged 4.0 liter XK8, 1997-2002. Highly recommended!Manufactured by XKs Unlimited. Use with 17-703-2444 cap. This quality radiator is made to original dimensions with modern alloy tanks and cores to improve cooling, save weight and look great. Supplied with steel frame as shown for bolt-in ease of installation. Applications:MK IMK II (not very late cars with BW 35 automatic transmission)3.4S/3.8S with manual transmissionNote: The original radiator used in late MK II and automatic transmission 3.4S/3.8S incorporates a transmission cooler. This radiator does not.