If individuals want to automatically refuse foreign mail or block all mail from a specific sender, they must submit a written request to the USPS to withhold correspondence for up to two years.
1 liter = 33.8140226 US fluid ounces. 1 US fluid ounce = 0.0295735297 liters. Note that this is for fluid ounces, not dry ounces. A fluid ounce is a measure of volume, just like a liter is. A dry ounce is a measure of weight.
One liter is equal to 33.814023 U.S. fluid ounces or 35.19508 British fluid ounces. Nowadays, a liter is 1000 cubic centimeters exactly. Multiply by 128 to get the exact number of US fluid ounces in a liter.