Size 3XL: chest 27.6 in / 70 cm, neck 17.3 in / 44 cm, back 21.7 in / 55 cm snug cut-measure the chest first and choose the larger size if your dog is between two. The shirt is sewn from 95 % soft cotton and 5 % spandex so air can circulate, sweat is pulled away, and every sprint, stretch or roll feels free and easy. Long sleeves guard against scratches, insects and post-op wounds, while the elastic hem lets you slide the tee on in seconds and keeps it in place during zoomies. Wear it year-round: it cools in summer, adds a light warmth layer in winter, catches shed hair in spring and fall, works as cozy pajamas at night, and stops licking so injuries heal faster. Whether the day holds couch naps, neighborhood walks, park play, hiking, camping, travel, training or beach runs, this single shirt keeps your dog comfortable, protected and ready for every adventure.