The new iPhone 7 and 7 Plus come with many changes, but one of the biggest modifications is they are the first generation of Apple smartphones that are water resistant. Both devices come with a IP67 rating, which means the smartphones are capable of withstanding a little over 3 feet of static water for up to 30 minutes.

“iPhone 7 and iPhone 7 Plus are splash, water, and dust resistant and were tested under controlled laboratory conditions with a rating of IP67 under IEC standard 60529,” says Apple, adding users should not attempt to charge a wet iPhone.

While the new generation of iPhones promises to be water resistant, the type of water it is resistant to makes a difference. Ocean water, for example, contains salts that can corrode the device.

Recently, surfer Kai Lenny tested out the water resistance of some iPhones (6, 6s, 7 and 7 Plus) for electronics warranty company SquareTrade. The iPhone 6 and 6s stopped working soon after coming into contact with salt water while the iPhone 7 ends up being okay, appearing to be functional, after 30 minutes of surfing. The iPhone 7 Plus, on the other hand, ended up with some audio issues.

YouTube user infohut put the devices through a stress test by emerging the smartphone in different liquids — water, soda, hot coffee — for five minutes. According to the tester, soda and coffee did not seep into the phone's seal and, in turn, the smartphone was not damaged on the inside. But when the device is placed in salt water, it only lasts 20 seconds.

In a follow-up test, the devices were immersed in soup, maple syrup, hot coffee, salt water, paint thinners, and dish washing detergent. The gadget held up while being spun in soup, viscous maple syrup, detergent, home brew beer and paint thinners. The tester also did a pressure test using a garden jet hose and shower water to find that the pressure triggered the digitizer but did not damage the phone.

Apple, which offers warranties that do not cover liquid damage, makes it a point to note that the device’s water-resistance may decline over time. “Splash, water, and dust resistance are not permanent conditions and resistance might decrease as a result of normal wear,” says Apple.