Metal sling swivel for VSR-10, which can be easily screwed into the hole in the front of the body of the weapon. For example, VSR from Tokyo Marui and JG have this hole.
Jing Gong, also known as JG or GB (Golden Bow), is a Hong Kong manufacturer of airsoft guns and parts. Jing Gong is one of the world's largest airsoft OEM (Original Equipment Manufacturer) factories with a long history of manufacturing and large production volume. JG focuses on the production of lower and middle price range guns.
Their line of electric guns is based on "clones" of higher-end brands, many of which are adopted from Tokyo Marui. Jing Gong produces many affordable but high performance AEGs.