From Manufacturer
The waterproof 1535AirTPF Wheeled Carry-On Hard Case in black from Pelican is a crushproof hard case made from lightweight HPX2 polymer that will protect and store sensitive gear. The case secures with an updated push-button latching system that uses compressive force to tightly clamp the case shut. This edition of the 1535Air comes with a hybrid insert that has both Pick-N-Pluck foam and a separate side divider section designed by TrekPak. This gives you the ability to maximize your protection for delicate gear and organize accessories in a single case. Carry your case using the overmolded handle or if it's too heavy, extend the pull handle and tow it behind you on its two low-profile, quiet-running wheels.
Your case is made of a super-light proprietary HPX2 polymer with honeycomb structural elements, which is up to 40% lighter than most other Pelican polymers. Case design features include an O-ring that seals it to an IP67-rating to make it dust and waterproof, dual 5/16" (8mm) diameter stainless steel reinforced padlock holes, and a pressure relief valve. This valve regulates the internal pressure, keeping your gear and the case from getting crushed and allowing you to open the case without having to break a tough pressurized seal that may develop. For easy identification, there's a polycarbonate card holder that may be placed on the front or side of the case.
As with all bags and cases, check with your specific airline for the exact measurements of what they consider "carry-on" luggage.