Anatomy of the Needle

The anatomy of the needle

The sharpened angular tip at the end of the needle. There are typically four types of bevels used for skin injections.

Made of stainless steel, which is siliconized to allow easier penetration, thus minimizing patient discomfort. Available in different lengths and gauges to suit individual clinical and patient needs.

Regular bevel: The most common bevel, used for a vast majority of applications. Typically used for intramuscular and subcutaneous injections.

Short bevel: The needlepoint geometry is designed to minimize unwanted injection depth, such as penetration through a vessel wall, and to obtain rapid withdrawal or dispersion of a fluid. Typically used for specialty applications such as arterial blood gas sampling and nerve blocks.

Intradermal bevel: The geometry of the tip is designed to allow for shallow and low angle insertion of the needle just below the epidermis. The fluid volume is typically very small and slowly administered. This unique needle bevel is used primarily for skin testing (e.g., allergy tests).

5-bevel: The two additional bevels create a flatter, thinner surface that has been shown to be less painful.*

There are three types of needle walls:

Regular Wall: This is the most common wall thickness. The thickness of the steel wall allows a good flow rate, and minimizes flexing when the needle is inserted into a vial stopper or patient.

Thin Wall: As shown in the diagram, the thin wall needle has a narrower steel wall, allowing a greater volume of fluid to pass through it. The flow rate is typically equivalent to that of a needle one gauge larger. This is especially important with very thin needles.

Extra Thin Wall: This has the thinnest steel wall, provides higher flow and requires less force to deliver medication.
Designed to protect the user from accidental needlestick injuries. Safety technology for injection needles includes retracting syringes, shielding needles and sliding sleeve syringes.

Designed to protect the user from accidental needlestick injuries. Safety technology for injection needles includes retracting syringes, shielding needles and sliding sleeve syringes.

Allows user to attach the needle to a syringe by either a luer lock or a luer slip connection. All safety-engineered needles are color coded to denote the gauge of the needle.