I'm 6' 380lbs. I measure 59" chest, 30" neck to waist and 24" arms. I bought a 4X 'navy'. It's really more of gray. I love this. Ribbed elastic waistband and wrists. The sherpa liner on the torso and hood and the quilted nylon in the sleeves keeps me toasty warm on 19 degree days. If you want to layer, order a size up. This fits great. Quality materials and craftsmanship.