Which preposition to use with flatiron

in Occurrences 2%

The burnishing iron should be heated and kept hot during the burnishing, about the same heat as a flatiron in ironing clothes.

at Occurrences 1%

I'd throw a flatiron at his head and put some castor-oil in his soup!" Joe laughed a little.

over Occurrences 1%

Often I've seen Maggy, holdin' up a batch of clo's, with pride just oozin' out of her, and heard her say, 'There ain't a person in these here United States that kin slip a flatiron over dry-goods the way my Pete kin.'

Which preposition to use with  flatiron