Security at one Las Vegas hotel where many DEF CON attendees are staying is searching rooms specifically for hacker tools such as Flipper Zeroes, WiFi Pineapples, and soldering kits, according to a copy of security’s instructions seen by 404 Media.

The document provides more specifics on what security at Resorts World see as potentially damaging items. When 404 Media first reported the room searches last week, the hotel explicitly linked the heightened security measures to last year’s ransomware attacks against MGM Resorts and Caesars.

“Housekeeping and Security will be tasked with conducting room checks on all stay over rooms daily,” the document reads. The document says that each day, the Housekeeping Assistant Director will print a list of rooms of people who booked a stayed through the DEF CON group block, with upwards of 1,000 rooms during the conference’s peak.