Be very careful as not everyone respects the norm of pin 2 as + and if they do not an adapter could cause damage by tying the ground to the wrong (hot) pin.
I have been referred to DIYcables and they show how to make an interconnect rather than using an adapter, so you dould customize a cable for your needs and avoid 2 unnecessary connections.
I have been referred to DIYcables and they show how to make an interconnect rather than using an adapter, so you dould customize a cable for your needs and avoid 2 unnecessary connections.