ONA Blocks are highly effective in eliminating airborne odors in small, confined spaces with limited air circulation. Lasting up to 30 days, they provide long-lasting odor control. Ideal for various locations such as closets, lockers, attics, cars, gym bags, kitchens, and more, the ONA Block is versatile and easy to use. Just remove the cap or make a few holes, then place it where needed. Measuring 3 x 3 inches (7.6 x 7.6 centimeters), it fits well in most spaces and continuously neutralizes unwanted smells.