You will receive a custom promo code to share with friends/family so that they can get a free room cleaning for trying Sweep. If they use your promo code, you will then get a promo code for your use to get a free room cleaning (valued at $28). For every successful promo code conversion, you will be given a different 1 time use promo code to get $28 off any future order you create. You may accumulate codes, but you cannot combine codes. These codes expire after 1 year.