I wear until they're threadbare and then replace
"I've had 6 of these shirts in the past 12 years and they're the greatest. The zipper allows heat regulation. They're the perfect weight of base layer because they block most sunlight in the summer without being hot like synthetics. (The feather weight merino wool shirts do not block the sun. ) They're silky soft and make cotton shirts feel like burlap. They're the perfect weight in fall or spring when temperatures fluctuate during the day. They're the perfect weight in winter if you're inside or as a base layer. They're machine washable and dry flat overnight. Pro tip- woolite and delicate cycle that uses enough water and they last. The dryer wears them out almost immediately."
