12v -> Arduino UNO DC Power Jack | VIN -> Monster Moto Shield

Hello

I want to use a 12v power source to run Arduino UNO and the Monster Moto Shield.

Can i use the 12v source directly to the Arduino DC Power Jack and then use the VIN and GND Pin to power the Monster Moto Shield?

The DC Power Jack is directly connected to the VIN without any regulation, is this right?

Thanks for your help!

The barrel jack is connected straight to the VIN pin.

There is a 1A rated reverse polarity protection diode in between them.
Make a splitter cable from the 12V source to feed them both. That will connect the grounds between them, and also keep too much current from going thru the diode.