Welcome to September, a month where #2 pencils and fresh notebooks hold all the promise of a new year. Instead of celebrating school supplies, we’re going to celebrate our gear this month: The most sentimental or memorable piece of gear, the one that makes you smile when you pull it on—or think about it.  Today’s piece is by Sarah Wassner Flynn. ( Read our previous posts here.)

When I first started running as a freshman in high school, my parents bought me a Timex Ironman Watch. Before that, my training routine was decidedly analog: I’d glance at the green-lit digits of the kitchen microwave clock before heading out the door, then check again when I returned. To calculate distance, I’d wait until my dad got home from work and have him drive the exact loop I’d run, me in the passenger seat watching the odometer. A little mental math—elapsed time divided by miles driven—and I had a rough approximation of pace.

But then, perhaps because my parents were tired of those after-hour drives, I received the watch. And though it couldn’t tell me how far I ran—GPS technology was still years away—it let me time my runs, take splits, and, of course, play with the cool Indiglo backlight. (I even used that soft blue glow to sneak in reading long after bedtime, holding the watch close to the page to illuminate one line at a time. The odd things you do as a kid!)

The watch was the men’s version, big and hefty on my narrow 14-year-old wrist. Wearing it felt symbolic of being a real runner. At the start of local road races, I’d glance around and see the same watch strapped to the wrists of the speedy adults. Knowing we shared the same gear made me feel cool and insider-y,  like we were all a part of the same club.

Sarah, today, with updated wrist tech.

That watch marked milestones.  My first run lasting more than 20 minutes. Then 45 minutes. And eventually, before my senior year, my first hour-plus run: a 10-miler at running camp, monotonous loops around a military base in Rhode Island. I don’t remember exactly how long it took, but I’ll never forget the thrill of watching the numbers tick over to 1:00:00. It felt like unlocking a new level of running, and a new level of confidence as a teenager on the edge of adulthood.

Once in a while, the numbers would fade, growing lighter until the screen went blank. I’d hand the watch over to my dad, who’d eventually replace the button battery with a mini screwdriver. Without my watch, my wrist felt naked. Runs felt amiss. Because even though I could trace my regular route with my eyes closed, I grew accustomed to knowing I could make it from my back gate to the twisty, rolling road I’d dubbed “Roller Coaster Road” in 10 minutes or less. That I could reach the neighborhood YMCA (often a turnaround point) in 20 minutes. That I could negative split my return trip, charging down the sidewalk leading to my back gate—my literal home stretch. In the chaotic time of adolescence, the numbers on the watch always gave me a sense of control.

By the time I got to college, Timex rolled out slimmer, more colorful models designed for women. Eventually, that big, gray watch was replaced with something pink and daintier. And later, a fancy GPS watch. But I never got rid of my first Timex Ironman. It’s still tucked away in a drawer, battery long dead. Because it’s more than just a watch—it’s a reminder of the time when running shifted from pastime to passion, from something I just did to something that helped shape me into who I am today.