It is well known that an EHC (Electrically Heated Catalyst) is very effective in reducing cold start HC emissions. However, the large electric power consumption of the EHC is a major technical issue. When installed in the exhaust manifold, the EHC can take advantage of exhaust heat to warm up faster, resulting in a reduced electric power demand. Therefore, a structurally durable EHC which can withstand the severe manifold conditions is desirable.Through the use of a extruded monolithic metal substrate, with a flexible hexagonal cell structure and a special canning method, we have succeeded in developing a structurally durable EHC.This new EHC installed in the exhaust manifold with a light-off catalyst directly behind it demonstrated a drastic reduction in FTP (Federal Test Procedure) Total HC emissions. Even after severe engine aging equivalent to 50,000 miles (850 °C x 100 Hours with a fuel cut mode), emissions continued to be reduced by more than 50 %, with less than 2kw of post heat, when tested in a 2 liter engine car.This low wattage and durable EHC can be a practical solution to meet LEV/ULEV regulations.