Abstract: A fastener includes a main body, a light guide, and a threaded securing member. The light guide is fit over the main body. The main body with the light guide thereon is fit into a mounting hole of a mounting plate and the threaded securing member engages a threaded section of the main body, whereby a top retention portion of the main body and the threaded securing member together establish abutting engagement that securely fixes the main body to the mounting hole. A light source unit is arranged in the threaded securing member and connected to a power source. Illuminators are mounted on the light source unit may give off light that is guided by the light guide to emit through a light emission portion of the light guide. Thus, the light emission portion of the main body may serve as a lighting ring for warning or indication purposes.