This looks like a lot of fun- the Super Soaking Fire Hose with Backpack. It has a water gun that can shoot a stream of water up to 35 feet. Since the water is stored in the backpack, it’s easier for smaller kids to carry around- and a lot cooler. Kids can pretend to be firefighters and spray the hose- at their friends. It also comes in an Astronaut Space Pack version:
Get one of each and have a firefighter vs. astronaut water fight in your yard.
Venture Pal Ultralight Lightweight Packable Foldable Travel Camping Hiking Outdoor Sports Backpack Daypack (Orange)