The hottest new accessory in the Hamptons this summer isn’t from Hermes or Loro Piana. It’s a clunky cell phone signal booster that exasperated Hamptonites are affixing to their cars to improve their reception in the notorious dead zone. “There is better cell service in Bangladesh than here,” one Sag Harbor resident complained to The Post.

The devices, made by companies such as weBoost, Wilson Amplifiers and Cel-Fi, sell for around $500. They have long been popular with truck drivers on long-haul cross country trips or adventurers traversing the Rocky Mountains. But now they’re in vogue with a more posh crowd.

But, there’s a hitch: The gadgets are bulky and ugly. They have not one but three parts. There’s a 7.

5-inch antenna — which can be extended more than three feet — that must be affixed to the outside of the car near the center of the roof. The wire from that antenna is then threaded into the car — either by awkwardly putting it through the window and rolling it up or by drilling a small incision into the roof of the car — where it is connected to a booster box that’s slightly bigger than an iPhone and typically rests on the back seat or floor. The box connects to a small internal antenna that can be mounted to or rest upon a car’s dash.

It works best if it’s 18 to 36 inches from where the cell phone being used (and hopefully boosted) is. The boosters can technically be installed by a car’s owner, but many opt to pay a mechanic a few hundred .