My baby needs milk every 3 hours at night. What is the best way to store milk in room temperature?

Are you able to direct latch your baby? If so, you don't need to store milk at all. You could get this Philips Avent Nutrient Preserving warmer which is ideal for heating and keeping breastmilk at its desired temperature. Otherwise, do get a thermal baby bottle from Pacific Baby - it can keep liquids warm for up to 10 hours. http://www.omigo.com.sg/pacific-baby-3i-pac113501906.html