A "shoulder holster" is a type of gun holster that is worn over the shoulder, with the gun resting on the side of the body. There are several synonyms for a shoulder holster, including "shoulder rig," "chest holster," and "underarm holster." These types of holsters provide a discreet and comfortable way to carry a handgun, making them a popular choice among law enforcement and civilians alike. They offer quick access to the gun and can help to distribute the weight of the firearm evenly across the body. So, whether you call it a "shoulder holster," "shoulder rig," or "chest holster," this type of holster remains a practical and effective way to carry a handgun.