Not really a single club but the transition to getting professionally fit by Titleist and matching up the 14 clubs to what works best for me, not just a standard set. The more you can forget about what is popular, or what the majority of people use, the better chances of maximizing your capabilities.

Upgraded to the new GT2 driver. Very accurate and increased my distance. What we are looking for. Worth going to see a fitter. First time hitting a regular shaft. Do not have to work as hard at the age of 78. Very happy.

Mine was going from a cheap distance ball because i didn’t believe a ball made a difference to finding a ProV1x in the rough at Torrey Pines North and experiencing what I could only describe as magic for the remaining holes.

Upgraded shafts without a doubt. Once I got fitted for the first time, and played a premium shaft vs the stock offering. it was an absolute game changer. I couldn't recommend this more!

For me it was adding the U505 3i to the club roster. Filled a gap perfectly and gives me confidence in what was an awkward yardage range with a prior club I didn't trust. The other club change was the putter. For decades I played Scotty blades. A buddy grabbed a Phantom (which never had my eye appeal) and I tried it one round and was blown away. Bought one the next week and have been shaving strokes ever since.

Lastly, Titleist's move to having the Left Dash part of the full time ball lineup was huge. From the first time I played the ball I loved it but when it was in limited production I felt like I was on a constant Easter Egg hunt to find my next dozen...now I just go to the Pro Shop when I need some. Big time confidence booster with that ball!

Whenever I made my most recent wedge upgrade I really notice the difference, I beat my clubs down so making that upgrade was huge for the fresh groves and new bounces. I haven’t upgraded my driver in 10 years so that answer might change when I do make that upgrade.

Simple, the Graphite Design Tour UB6. I was just going to go with a stock shaft during my GT3 fitting, but my fitter asked if I wanted to try some upgraded shafts. At first I said no, but after several shots, I took him up on his offer. That shaft made such a difference from all of the off the rack new releases over the last 5 cycles that simply did not fit my game. I have since added the Graphite Design shafts to my GT 2 4 wood, GT2 7 wood and GT2 hybrid. Golf is fun again!

A bigger cooler to hold more adult beverages