I have a set of 21 Stud Flathead Pump-In-Heads Aluminum Heads. One is marked 40-6049-A2 with HT and FORD. The other has no markings, and appears NOS. From my research I believe the unmarked head is a repro made in Australia. The Ford head has been refurbished and milled. It has a two spots on the head that show repair, but still need a little fine finishing to make perfect. The combustion chambers are the later type, and I heard they are similar to the RICARDO chamber from Model A heads. $450 for the set and price includes shipping.