I don’t know why Titleist has not responded to this inquiry. It’s a simple question to answer based on the new Titleist irons. Would the new T150 fill the build for the new 3 and 4 iron? As mentioned on the original post, my 3 and 4 irons are easier for me to hit. Hybrids are not my cup of tea.

The T300's are Titleist's game improvement iron for 2021. The new T350's are the new version of their game improvement iron. The problem is the 3-iron isn't available in the T200's, 350's or 400's. And a 4-iron isn't available in the 400's.

Given the 350's and 400's clubs are designed for the improving player you're not likely to have the game to stroke a 30 or 4-iron.

The likely alternative would be the T200 (Utility) available in 2i (17°), 3i (20°), and 4i (23°) or the U505 available in 1i (16°), 2i (18°), 3i (20°), and 4i (22°).

How did you end up in the T300's? A Titleist fitter will have the utility options in their test set. You could get a T200(U) in the 4-iron and a U505 in the 3-iron.

A mixed set could offer you the range of utility that you're looking for.

Side note, I was fitted by a Titleist fitter and ended up in a TSi 4H and for the life of me I just cannot replicate the success that I had during the fitting. I'm contemplating working into a T200(U) to replace the 4H.

Fortunately, Titleist has plenty of options to suit your game and gapping.