Have you ever bought a piece of band merchandise and noticed a mistake on it? Mike Portnoy has, and it was a typo on his own band's merch — but he didn't catch it for eight years.

The drum legend uploaded a selfie on Twitter, where he was wearing a zip-up sweatshirt from The Winery DogsDouble Down world tour that took place in 2015 and 2016. The paw logo and text, located on the left side of the front of the sweatshirt, reads "2015/2106," and Portnoy made a shocked facial expression to show his surprise.

"I pride myself on how meticulous & anal I usually am with overseeing every details of all the merchandise, artwork, layouts, etc. for ALL of my bands... Imagine my surprise when I only NOW just realized the typo on this Winery Dogs hoodie that I’ve been wearing for the last 8 years!"

See the tweet below.

"Oh my god. That's a long tour!" someone responded jokingly, while others noted that would be a 91-year trek.

"Not a typo. Just a long tour. Still shorter than the final KISS tour, but still long," another fan replied.

The Winery Dogs are one of Portnoy's many musical projects. The supergroup, which also features Richie Kotzen and Billy Sheehan, was formed in 2012, so the 2015/2016 tour referenced in Portnoy's photo was likely in support of their 2015 sophomore album Hot Streak. 

READ MORE: The Winery Dogs' Mike Portnoy Plays His Favorite Drum Intros — Watch

The rockers just wrapped up a North American tour earlier this month, and have another round of shows coming up soon in South America, the U.S. and Europe. See all of the dates here.

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