WASHINGTON — Tennis balls are out. So are explosives, large knives, gas masks, umbrellas with metal tips and water guns.

But real guns are OK.

There's a lengthy list of what to avoid taking into downtown Cleveland's 1.7-mile "event zone" during the Republican National Convention in Cleveland on July 18-21.

Firearms are allowed because Ohio is an open-carry state, meaning it's legal for adults to freely carry guns in public without licenses. People interested in carrying concealed firearms can obtain licenses to do so if they are older than 21 and legal U.S. residents without criminal histories.

While it's allowed to have a loaded firearm within the "event zone," it's forbidden within the "secure zone." That includes the Quicken Loans Arena, the convention's main site, and several blocks around it regulated by the U.S. Secret Service. Several roads near the arena will be closed during the event.

The restrictions aren't limited to the ground, either. City officials and federal agencies said Cleveland and surrounding communities would be "no drone zones" under Federal Aviation Administration flight restrictions during the convention.

In March, the Secret Service announced that convention attendees can't bring firearms into the arena after a petition on Change.org that sought the right to bring guns into the arena got nearly 46,000 signatures.

Here's a partial list of items banned from downtown Cleveland during the convention:

  • Weapons. That includes air rifles, air pistols, paintball guns, BB guns, pellet guns, blasting caps, switchblades, knives with blades 2 { inches or longer, blackjacks, swords, sabers, hatchets, axes, slingshots, metal knuckles, nunchucks, mace.
  • Projectile launchers. That includes water guns and water cannons.
  • Household items. Among them are ladders, glass bottles, ornaments, light bulbs, aerosol cans, ceramic vessels _ and any other fragile container, regardless of whether it holds any substance _ non-plastic containers, bottles, cans, thermoses, umbrellas with metal tips and tennis balls.
  • Camping equipment. Prohibited are tents, sleeping bags, sleeping pads, mattresses, cots, hammocks, stoves, coolers or ice chests, backpacks and bags exceeding 18 inches by 13 inches by 7 inches. Backpacks also will likely be searched, according to Dan Williams, Cleveland's media relations director.
  • And these other items: drones, lasers, containers of bodily fluids, sound amplification equipment, gas masks other than those used for medical oxygen, grappling hooks, hammers, sledgehammers, crowbars, ropes, chains, wire, string or tape longer than 6 inches.