Pete Wentz flew to Japan for some event on Friday ... but left his wedding ring at home.
Earlier this week, the 31-year-old reunited with his estranged wife Ashlee Simpson for a little Valentine's Day lunch.
But Friday, Pete didn't put a ring on it, so it looks like he's single, ladies.
Pete Wentz -- Look Ashlee, No Ring!
2/18/2011 1:00 PM PST BY Johnny Lopez
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