Home Page   |   Online Store   |   Color Selections   |   Construction   |   Comparison   |   About Us   |   Contact Us Spa Cover World Home Page Online Store Color Selections Construction Comparison About Us Contact Us General Information Spa & Hot Tub Safety Tips Maintaining Your Spa Cover Spa & Hot Tub Care Spa & Hot Tub Resources Choosing The Right Spa For You Choosing The Right Location For Your Spa Filling Your Spa – Balancing The Water Spa Practices – Keep It Hot Or Not! An Air Injector And A Jet - What's The Difference?   Air Injectors vs. Jets – What the differences are. Air Injector Air injector spas and hot tubs are found in the seats of the spas. You will notice that many seats have small holes and these holes are the air injectors. This is where the air comes through to create the bubbles that you see in spas when the injectors are turned on. Jets Spa jets are the ones that you usually see on the sides, near neck rests and in other key points of your spa or hot tub. Jets are used for massaging the shoulders, back, legs, arms and feet. Jets in hot tubs are used for hydrotherapy and can be adjusted to the soaker’s liking. Many jets are interchangeable and can be removed during cleaning.