I don’t know much about this company (perhaps they’re new?) but this Senses Saturn 50W box mod looks pretty good. It is variable voltage and variable wattage with a range of 2 volts to 9 volts in voltage mode and 5 watts to 50 watts in wattage mode. You can switch between these modes by pressing the fire button quickly 3 times or 5 times to turn the device off or on. It has a minimum resistance of 0.2ohms and a spring loaded brass 510 pin. It holds a single 18650 battery which can be accessed from the back cover. The cover clicks into place and is removed by pressing the button on the back of the device.

Details:

Variable voltage: Can be adjustable from 2V-9V (in 0.1V increment)
Variable wattage: Can be adjustable from 5W-50W (in 0.1W increment)
OLED screen display the output wattage, battery level, output voltage and resistance
Quickly press the fire button 5 times to turn on/off
Quickly press the fire button 3 times to switch the VV/VW mode when the battery is turned on
Compatible resistance range: 0.2ohm-2ohm
Protection system:
– Atomizer short-circuit protection
– Over-charging protection
– Over-discharging protection
– External short-circuit protection
– High temperature protection
Recessed 510 threading connection (with spring-loaded brass center pin)
Side mounted firing button, without locking ring
Houses single 18650 battery (battery sold separately)
Push the back button to open/close the back cover
Micro-USB charging port