Uses T-Hooks mounting but also compatible with AMPS 4 screw mounting Compatible with Onyx Series Radios, Edge Radio, Xpress series with use of different power supply Not compatible with Stratus, Starmate, or Sportster radios XDPIV2 SiriusXM XDPIV2 replacement cradle with T-hook mounting. If you currently have a T-hook mounting, then this is the cradle for you. Will also work with the AMPS 4 screw mounting system. Works with the Onyx Series radios, and the Edge. Will also work with Xpress series radios, but would require a different power supply. Does not work with Stratus, Startmate, or Sportster Series radios. This will work with Both T-hook and 4 screw AMPS mounting systems !!!