Larry, I think Titleist uses size .355 shafts. I have the Zelos7 on my 716 CB.

The custom catalog doesn't list the Zelos-7 (75 g) as an available option. Titleist might consider it as an exotic option - you'd need to call Titleist. You can certainly swap it out at your local golf shop as an aftermarket change. The steel shafts in the catalog are all 85 g and up. The TT AMT-Red worked great for me to move from the 65 g graphite options for my AP3 order. Better than the XP-95. You can try that option from any Titleist fitter.

Hi Larry, Yes, we can use the Zelos 7 in any Titleist iron head. They weigh about 77-78 grams in an S flex and about 73-74 gr in a R flex.