My son used this for 3 months and aded 5+ inches to his vertical - went from barely touching the rim to dunking with ease! Much safer that barbell squats - and can be used anywhere.
This system is highly recommended and proven to work very well. The item "Jump USA Squat Flex Vertical Jump Building System Excellent Condition" is in sale since Wednesday, December 20, 2017. This item is in the category "Sporting Goods\Team Sports\Basketball\Training Aids".
The seller is "chamama" and is located in Flora Vista, New Mexico. This item can be shipped to United States.