These recycled microterry hoodback slippers from Acorn feature an innovative environmentally friendly technology that takes eco-savviness to the next level. The versatile indoor/outdoor outsole uses Bloom™ algae foam - a substance which reuses harmful algae, turning it into a safe and stable compound. The recycling of this material helps reduce CO2 emissions and protect freshwater sources used by plants, animals and even humans. Machine washable in cold water; air dry.