It is .355.
C03 at 35 inches will run between 330 and 335 grams. Mine is 333. I would suggest adding some lead tape to the sole. I buy the Golfsmith lead tape that is 1 inch wide rather than the more common 1/2 inch tape. Adding just one layer to the sole of my C03 brings the weight up 7 grams to 340 total, which is my preferred weight. Adding two layers would take the weight to 347. It looks very good too--it just looks like a blank sole putter.