Please remind me of the polarity of car-type cigar lighter adaptor

[shmoo]

I know they are next to useless but we have a variety chargers for phones, search lights and stuff so we need one. I made one up ages ago on a trailing lead but its fallen apart. I am sat here, soldering iron in hand, but have forgotten if the center is +ve or -ve

 

[alan17]

Centre +ve

 

[westy_two]

center is + ve, fuse is on the center which in on + side

 

[shmoo]

Thanks folks.