No more filling and carrying heavy sandbags—just add water to these flat, lightweight barriers, and they expand to block flooding. They reach full size in about 10 minutes and hold their shape for 2-3 months. Use in front of areas you want to divert water from, such as entrances and ramps. The fabric covering is UV-, tear-, and puncture-resistant, so they hold up well outdoors and on rough surfaces, such as pavement. They are nonhazardous and can be disposed of in the trash. Do not use with salt water.