Gear Review: Smartwool Arm Warmers

Transform your shortsleeve tee to long with these cozy add-ons.

For 1.5 ounces, turn any T-shirt into a long sleeve. SmartWool Arm Warmers are bicycle-chic (or bicycle-dorky?) but effective—letting you avoid overpacking and frequent changing in variable weather. $25; smartwool.com