SOFTNESS AGAINST YOUR SKIN: These One-piece thermal union suit is made of 48% cotton, 48% rayon, 4% spandex, ultra soft to sleep in, warm enough to lounge around the house and stretchy fit for most body types FUNCTIONAL BUTTON-UP CLOSURE DESIGN: The one-piece pajamas features full-button placket to easily put on and take off; Rear fly opening for convenience SINGLE-PIECE FITTED UNION SUIT: One piece thermal gives complete body warmth and reduces buck, making it perfect for layering PRACTICAL USE FOR ANY OCCASIONS: Long sleeve onesie in double-layer thermal; Keeps you warm in cold outdoor working, cycling, hiking, skiing or other winter activities, living or traveling to cold places THOUGHTFUL EVENT GIFTS FOR FAMILIES: If you are looking for adult onesies pjs that would be comfortable to get ready in, cute for a humorous family photo, ideal onesie undergarment for warmth Men's Cotton Thermal Underwear Union Suits Henley Onesies Base Layer