No more tripping over things in the dark — these light-up slippers have built-in LED lights to safely illuminate your path. Slippers with lights are perfect for middle of the night trips to the bathroom or kitchen. Weight sensors alert the lights to activate when you put the slippers on. Illuminates 20 to 25 feet in front of you and stays on for about 15 seconds. LED bulbs run on lithium ion batteries that can light up to 20,000 times per battery life. These light up house shoes are a comfortable, safe choice for men or women. Neutral styling and unisex fit: SM fits women's shoe size 7-8, men's 5.5-6.5. MED fits women's 8.5-9.5, men's 7-8. LG fits women's 10-10.5, men's 8.5-9. XL fits women's 10.5-11, men's 9-9.5. Made from TPR/polyester.