Water balloons

A water balloon or water bomb is a latex rubber balloon filled with water. Water balloons are used in a summer pastime of cooling off through water balloon wars. Water balloons are also popular for celebrations, including celebrating Holi and Carnival in India, Nepal, and several other countries.

Gas balloons (air or helium types) may be used as water balloons, but are not typically preferred because the balloon wall thickness is different. A water balloon is designed to be filled up to the approximate size of a baseball in a pear shape (so as to be thrown more easily), whereas some gas balloons, when filled with water, may reach the size of a basketball; this is disadvantageous because those balloons are harder to handle, usually requiring two hands. Mainly for safety reasons, water balloon walls are designed to be thick enough to be held without bursting yet thin enough to burst upon impact.

In a similar process to gas balloons, water balloons may be molded into various shapes at manufacturing. One process involves a patented mandrel for making elastomeric articles.

Water balloons are common in sizes from an inch and a half to four inches though larger sizes are available. Typically water balloons are sold in quantity and often include a filling nozzle in the packaging. Many of the low cost brands use small water balloons and generic nozzles which both tend to be difficult to use.

Another form of water bomb is a sheet of paper folded to form a roughly spherical container (Origami) capable of holding water. These are then filled and used in a similar way to latex versions.

Water balloons are typically filled at an indoor faucet, an outside tap, or at the end of a garden hose. Multiple types of filling nozzles are available on the consumer market and come in threaded (3/4" standard in the US) and non-threaded types. Non-threaded nozzles are called filling funnels and may be difficult to use. Some brands of nozzles are called loader instead of nozzle, but no differentiation exists between other types of nozzles. Nozzles may include a valve feature for turning the water source on or off as needed.

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Wikipedia