In General: The basic versions are specific for size, if you are between sizes - choose the large. The magnetic version: use 3 layer for height up to 5'-10" and the 4 layer for 5'-10" and taller.

If you have a neck size of 14 inches or smaller, the basic small will give the best fit and is recommended for smaller individuals.

Air Neck Traction Specifications Small Basic
Basic Small		 Large Basic
Basic Large		 3 Layer Magnetic
Magnet 3 Layer		 4 Layer Magnetic
Magnet 4 Layer
Neck Size 10" - 15" 16" - 22" 11" - 19" 11" - 19"
Traction Range 0.4" - 9.2"
 0.4" - 9.2" 0.4" - 8.4"
 0.4" - 10.8"
Traction Force 0 - 180 lb 0 - 180 lb 0 - 176 lb 0 - 176 lb
Air Chambers 3 3 3 4
Magnets 0 0 3 3
Reversable Yes Yes No No
Valve 1 Roller 1 Roller 2 Ball 2 Ball

For the Magnetic Air Neck Traction Models

Although the magnets are small, persons with pacemakers, defibrillators, implanted insulin pumps or other electromedical devices should keep magnetic therapy products at least eighteen inches from the device. Use should also be suspended during pregnancy. Keep magnets away from computer disks, audio/video tapes and credit cards.