According to the invention there is provided a needle assembly (1) for mounting on an injection device. The needle assembly comprises； a main body (10) configured to be removably attached to the injection device in use and a needle (90) is secured in the main body (10) having a forward portion which projects forwardly from the main body. A shield (60) is pivotally connected with the body portion by a hinge portion (80). The shield (80) is rotatably movable between: a first position, in which the forward portion of the needle (90) is exposed for use, and a second position, in which the shield (60) is positioned over the forward portion of the needle (90) such that the forward portion of the needle is substantially enclosed within the shield. The shield (60) comprises a pair of spaced apart side walls (64, 66). The base of the side walls comprise a first cooperating feature (72, 74) for engaging a second cooperating feature (22, 24) of the main body (10). The cooperating features are configured to engage to hold the shield in its second position independently of the hinge.
