Keystone module
（重定向自Keystone jack）
![A keystone module for a CAT5 network cable](/Images/godic/202501/22/Keystone_module_CAT5_orange1907.jpg")
![A 3-port keystone wall plate](/Images/godic/202501/22/Keystone_wall_plate1908.jpg")
![](/Images/godic/202501/22/Assortment_of_keystone_modules1908.jpg")
A keystone module is a standardized snap-in package for mounting a variety of low-voltage electrical jacks or optical connectors into a keystone wall plate, face plate, surface-mount box, or a patch panel.
Keystone modules have a rectangular face of 14.5 mm wide by 16.0 mm high and are held in place with flexible tabs. This allows them to be snapped into a mounting plate with correspondingly-sized rectangular holes, called ports. All keystones, regardless of the type of jack they carry, are interchangeable and replaceable. This provides much flexibility in arranging and mounting many different types of electrical jacks in one plate or panel without requiring customized manufacturing.