Gett, the black cab app, has launched a series of ads brazenly criticising Uber’s surge pricings, assuring riders that black cabs would never charge such a thing. And it’s not the first time it’s lashed out at Uber.

The app has launched a billboard campaign in New York that takes direct aim at rival Uber for being too expensive, with the ads also popping up across phone kiosks, bus shelters, digital panels, and almost 600 subway cars.

“You didn’t know what surging meant until you knew what Uber meant,” says one of the billboards, while another claims, “Uber hates us because we’re surge-free. And probably because we’re beautiful”.

The ‘surge’ Gett refers to is the automatic price increase apps like Uber and Lyft charge during busy periods when demand for a ride is particularly high. The aim is to encourage more Uber drivers to hit the streets and help ease the load by promising them higher rates.

You can check out some of their sassy slogans here: