surface of the plastic manifold 20 an elastomer filter seal 80 is provided between the plastic manifold 20 and the steel plate 70 in use the sandwich solenoid manifold assembly 10 would be affixed to an automatic transmission device 12 as shown in fig3 and disposed in the oil sump chamber of the transmission the automatic transmission device 12 has a plurality of threaded bores 14 for receiving fasteners not shown for fastening the sandwich solenoid manifold assembly 10 to the transmission 12 the plastic manifold 20 includes a plurality of insert receiving holes 22 the insert receiving holes 22 are provided with a radially recessed upper rim portion 22a a plurality of lower steel inserts 40 are inserted in the insert receiving holes 22 of the plastic manifold 20 the lower steel inserts 40 are provided with a cylindrical body portion 40a and a radially extending flange portion 40b at an upper portion thereof the radially extending flange portion 40b of each lower steel insert 40 is seated in a radially recessed upper rim portion 22a of the insert receiving holes 22 as will be described herein the lower steel inserts 40 receive a bolt therethrough for fastening the sandwich solenoid manifold assembly 10 to the transmission 12 the steel inserts are designed to absorb the forces from mounting the sandwich solenoid manifold assembly 10 to the transmission 12 and thereby allows the use of a plastic manifold 20 the plastic manifold 20 optionally includes a plurality of integrally formed upward extending portions 24 for receiving solenoid valves 30 in.