If you’ve disembarked from the L at Bedford Avenue, you’ve probably seen him: the ruddy-cheeked guy handing out “Amazing Eyebrows” postcards. You may well have thrown one away — frayed images of the model with henna on her back resurface all over the streets of North Williamsburg. The thing is, Amazing Eyebrows really is amazing for eyebrows. The no-frills space (one of two Amazing locations; the other is on Graham Avenue) looks loosely clinical, but for the Bollywood music blasting through the sound system. The staff is warm and friendly, and despite the flyering, the clientele is peppered with regulars. Threading, like waxing, is never painless, but the ladies here are gentle and produce shapely brows for just $6. In a city where eyebrow grooming might run you as much as $65, that’s a steal.