The Bulldog ST Delta L Airsoft Guns are electric Sportline BB Guns. Outstanding PRO-level rifles have many great features not found on an airsoft rifle at this price. These AEGs (electric guns) have a high-quality motor and internal parts, metal bushings, adjustable hop-up for greater accuracy, Nylon receiver to reduce the weight and deliver a custom moulded grip, high-end steel gear set. These Sportline ST Series airsoft guns from BULLDOG will NOT disappoint.