You'll love the cool, comfy feel of our cool nightsâ® tank sleepshirt, designed using our cool nightsâ® fabric that stays cool to the touch. The sleeveless, scoopneck styling is perfect for warm nights, helping to keep you comfortable for a great night's sleep. Detailscool nightsâ® fabric is made with lightweight rayon fibers that stay cool to the touch and keep the fabric from sticking to your body. Scoop neck. Sleeveless. 36 from shoulder. 93% rayon, 7% spandex. Machine wash. Imported.