The main difference between the PRO version and the usual one is the port for the fiber optic cable and the ability to control the aperture wheel located on the front side of the camera.
40M/130FT Underwater camera housing for Sony A7R IV (Black)
Full camera control is available, except for the joystick.
SeaFrogs 6" optical acrylic Dry Dome Port V.7
6" Dry Dome Port V.7 with a lens shade. Created specifically for underwater photography.
The primary application of this underwater housing is underwater photography/videography. However, it can do a lot more by protecting your camera from weather hazards such as rain, dust, snow, etc. Because of its compact size and nearly all functionality, it is an ideal item to have while traveling.
Compatible lenses (Dome port)
Samyang AF14mm F2.8 FE and Sony FE 28mm F2
Sony FE 28mm F2 + Fisheye Converter
Sony FE PZ 16-35mm f/4 G (Autofocus only, Manual zoom gear included)
Compatible lenses (Standard port)
Sony FE 16-35mm F/4 ZA OSS (Autofocus only, Manualpurchase here) - Works from 17mm to 35mm
Sony FE 24-70mm F/4 ZA OSS (No zoom available, use at 24mm only)
Sony FE 24mm F1.4 GM (No manual focus available
Sony FE 28-70mm F3.5-5.6 OSS (Autofocus only, Manual zoom gear included)
Sony FE 50mm F1.8 (No manual focus available)
Sony FE 35mm F1.4 GM Lens (Autofocus only)
Sony FE 50mm F2.8 Macro (No manual focus available)
Sony FE 55mm F1.8 ZA Carl Zeiss Sonnar T* (No manual focus available)
Sony FE 85mm F1.8 (No manual focus available)
Materials :
Polycarbonate
ABS plastic
Optical glass
Stainless steel
EPDM rubber
O'ring sealed buttons with spring
Optical acrylic
Key features:
Vacuum Pump System port
Inbuilt leak detection sensor
Interchangeable port system
Synchro cable port
Dual Fiber-Optic port (Sea&Sea type)
Standard flat port (Optical glass)
6" Dry dome port (Optical acrylic)
Stainless steel mounting plate 1/4" Thread
40m / 130ft Dept rate
The reinforced metallic bottom plate
In order to connect an external strobe with this housing, it will require to use of a Dual 5-Pin Sync Cord (purchase here) or a Single 5-Pin Sync Cord (purchase here), or a Fiber-optic cable (purchase here) with a Flash trigger (purchase here)
Compatible lenses & ports list 
