Rats are so common in the city, many New Yorkers fancy themselves as rat know-it-alls.

“Well, they have the subway rats – I call them the Mutant Ninja Turtles - and they have the local neighborhood rats,” said Indigo Allen, a resident of Brownsville, Brooklyn.

Brooklyn Borough President Eric Adams says he's become an expert too - and not just because Brooklyn residents made 6,500 rat complaints to 311 last year, more than any other borough. Adams says he’s been learning all about rats because the rodents have been plaguing Borough Hall, digging telltale burrows outside the building.

“If you’re feeling as though you’re seeing an increase in rats, it is not your imagination. It is real," he said.

On Thursday, Adams summoned reporters to witness a new weapon in New York’s battle against the pests - a boxy contraption called the Rat Trap that lures the rodents with nuts and seeds, traps them and drops them to their demise into a vat of alcohol and other liquids. Several of the devices were placed outside Borough Hall a month ago.

“There’s a very sensitive switch here, drops them into the bottom and they’re contained in there,” said Rat Trap, Inc. President Anthony Giguinto, explaining the device to reporters.

“There’s no scent. There’s no smell.  There’s not spreading bacteria. They’re contained in the unit until we clean them out.”

But the process is not for the faint of heart. At the press conference, a Rat Trap worker used a spatula-like tool to scoop out the dead varmints one-by-one from the Rat Trap vat and place them in a plastic bag. The sight of so many dead rats stewing in the vat's liquid solution had many reporters looking away.

Adams said the vat contained 30 days of dead rats. He pronounced the test a success.

"It did the job of what we needed done," he said.

Adams says this is a better solution than the city's $5.5 million program of spreading bags of poison pellets.

“To rats, this is a joke,” he said, holding one of the bags for cameras

Still, some doubt the new contraptions would solve the city’s rat infestation.

“I don’t care if that box costs 4 cents or $400. The reality is that it will not work comprehensively for our city, because there is no comprehensive plan,” said Carol Morrison, an organizer of the Prospect Heights Rats Action Task Force.

Adams said Rat Trap, which is based on Long Island, approached his office with the idea for the free test of the traps. The company normally charges $300 to $400 a month per trap, which includes removing the dead rodents.

Adams said he will use an unspecified sum from his budget to continue the test at an undisclosed public housing complex, and in Bedford-Stuyvesant.