I'm 5.8 and weight 150 Lbs and this jacket fits me perfectly. I usually buy Medium but Burton's sizes are 'always' bigger. If you're a medium then Small would be the. best choice for you. Check Burton's size chart for reference. Used 'Like New' Only used a couple of times Snowboarding Jacket This workwear-inspired jacket does more than you can imagine. The Burton Dunmore Jacket features DRYRIDE™ 10,000mm / 10,000g waterproofing and breathability along with lightweight THERMOLITE® insulation and Living Lining® for automatic climate control. A serious trifecta for getting work done on the mountain.