Emergency Service Unit, which is capable of conducting rescue operations. Armor and vests Uniformed police officers often wear body armor, typically in the form of a lightweight Level IIA, II or IIIA vest that can be inconspicuously worn under uniforms, though some departments allow vests to be worn above uniforms with rigs and pouches installed to replace the typical duty belt. Lightweight level IIA, II or IIIa vests are generally capable of stopping most handgun rounds. SWAT teams typically wear heavier Level III or IV tactical armored vests, often with steel or ceramic trauma plates, comparable to those worn by U.S. military personnel engaged in ground operations. Level III or IV vests are more capable of protecting officers from rifle rounds. Officers trained in bomb disposal wear bomb suits designed to protect them from the effects of an explosion when working around live ordnance. Local police foundations have also initiated programs to provide law enforcement agencies with higher level vests that provide greater protection and vests for police dogs. Body-worn camera Multiple states, such as California, Washington, and Illinois, among others, have pending body-worn camera legislation that requires its police officers to be equipped with body-worn cameras when the officers are on duty. Body-worn cameras are video recording devices around three inches long that cost between $129 and $900. There are different body-worn camera models, but a standard body-worn camera includes an on and off switch that enables the image capturing technology to record and store data in the cloud. Body-worn cameras have become standard due to the rise of complaints about police brutality across the nation. Supporters argue that the use of a body-worn camera allows evidence to be viewed from an unbiased perspective. Body-worn camera models are being developed that are intended to resolve the technology's limitations, such as better audio capturing technology and battery life. Drones In recent years police have recruited unmanned surveillance devices such as small throwable robotics and flying drones to conduct reconnaissance in dangerous locations. These devices can be used to identify the presence of a hostage, locate and/or identify subjects, and reveal the layout of a room. The devices do all this by transmitting real-time audio and video to the pilot, giving police an advantage when they cannot directly see a suspect or enter a location where they are needed. Some other uses for this device may be bomb detection, as well