Syringes consist of a plunger within a small, hollow tube that function as small piston pumps that are used for injecting or withdrawing fluids and that are often utilized in the medical industry. They are sometimes attached to a hypodermic needle in order to inject drugs or withdraw fluids from the body and are often disposable. Due to the material's hygienic nature, syringes are usually made of either glass or plastic in order to be transparent, but utilize stainless steel needles.

Besides being hygienic, stainless steel syringes offer many other benefits for medical applications such as blood transfusions, blood testing, venom extraction and insulin shots. Some of these other advantages include ease of cleaning and the requirement of little to no maintenance. They also offer fine points and special coatings that help to make injections as easy and painless as possible. Because they are so small, syringes are able to reach areas that are usually otherwise inaccessible. However, there are various applications for syringes other than in the medical industry. Syringes can also be used in non-medical laboratories, cooking, to refill ink cartridges, and in other products and industries.
Syringes are a common example of small diameter tubing. Often utilized in conjunction with hypodermic needles, small diameter tubing is a type of stainless steel tubing that is used in equipment found in medical and dental applications, including those used in minimally invasive procedures. A syringe is typically constructed of a plunger in a hollow tube that functions by way of the plunger pulled or pushed up and down inside the tubing. The pulling and pushing allows the syringe to either expel or take in gases or liquids. One end of the tubing is closed, while the other end is open. The open end is typically outfitted with either a nozzle, tubing or a hypodermic needle that all can be utilized in order to direct the flow of materials into or out of the stainless steel tube. There are two main types of syringes: disposable and non-disposable. Disposable syringes are constructed from plastic, and are typically formed from polyethylene for increased corrosion and chemical resistance. Non-disposable syringes are typically fabricated from glass. These syringes offer a higher degree of precision. Additionally, syringes generally measure less than or equal to 0.188 inches in outside diameter.