Yes it is Docter/Noblex standard, I just tested it, it is specific for berreta apx. Please note that this mount replaces your rear sight, option for slides that come without RDO, the mount comes with the hole for the pin that comes out above the slide (automatic striker block safety), It has two holes for screws and four sockets in which the pins on the mount/adapter fit, one in each corner. There is a wide range of mounts for this footprint on the market.
Some compatible models:
Docter/Noblex Sight C
Docter/Noblex sight 2+
Docter/Noblex sight III
Docter/Noblex QUICKsight 5.0 VR
Noblex Sight G
Vortex Viper
Vortex Venom
Sightmark Mini Shot M-Spec
Leica Tempus
MAKdot 1×25
Vomz Pilad 1×20
ADE Advanced Optics RD3-006B Huracan
ADE Advanced Optics RD3-009 Crusader
ADE Advanced Optics RD3-012 Delta
ADE Advanced Optics RD3-013 Bertrillium
Burris Fastfire 2*
Burris Fastfire 3*
Delta Optical MiniDot*
Delta Optical MiniDot II*
Hawke Reflex 1×25*
Vector Optics Frenzy 1x20x28*
Sightmark Mini Shot Pro Spec*
US Optics DRS 2.0*
US Optics DRS 2.0 Enhanced*