RAIN Eye Mask Self-Heating Warm Compress delivers gentle, self-heating warmth to help relax eye strain and reduce puffiness. It supports healthy tear flow and is the perfect way to unwind after screen time, travel, or long days — no microwave needed. Each mask warms up in seconds and stays comfortably heated for 20+ minutes to help soothe tired lids and promote calm. 1 box contains 20 self-heating masks (air-activated).