More than likely it was a newer version of the ball you listed on profile page

Titleist doesn't usually tell, but the mystery is half the fun of being a tester and keeps you unbiased.

I too used the test ball and loved it and want to find out which ball I used. Normally I use the NXT tour S. Was this the new version of that ball?

i was a test golfer for titlist,i don't know which ball i was testing but i got about 10 yards off the tee,and when i hit the green the ball held pretty good.I would play this ball all the time. Thanks for asking me to test the new ball.

I've asked also, and not gotten a reply. My test was in Mich. and a bit cool out. Headed to Fla. in a couple days, liked them here but want to hit them in 80 deg. weather.

What become the Square golf ball and triangle golf ball

I as well was one of the Team Titleist testers. Was the Velocity, or DT Tour the ball we tested. I would like to purchase enough stock for the year. R & D, now's your chance to sing out. Regards, Gary N.

This is an educated guess but I believe the square ball is a ProV1x and the triangle is a ProV1. I looked closely at the dimple pattern of the two against the ProV1's I normally play and, while the differences are subtle to the eye, there are differences. Secondly, the square ball is consistently longer with less spin; especially with driver which for me is the easiest shot to discern the difference. What I found most interesting is that the finish of these balls appears brighter and the actually roll smoother on the greens. I found this last trait astounding. I always thought a ball is a ball on greens. Not so apparently. Even my playing partner noticed that aspect.