You just screw this spring onto the power supply and it will protect the cord where it connects to the power supply. It threads onto the large part of the cord where it comes out of the power supply. It threads by hand and really grips tight. A new power supply is $24.00 plus $8.00 shipping, so this small investment may save you a lot of money. I have had a lot of power supplies fail in the past and all of them were due to stress where the cord connects into the power supply.
The spring is $1.00 plus $1.00 shipping and handling. You can send cash to 725 Snapp Bridge Rd. Limestone, TN 37681 or PayPal me the two bucks to my e-mail address.
A WORD OF CAUTION; This spring fits my PHIHONG Model PSAA20R-240. It may not fit another model of power supply. The part that it screws onto on my power supply is 5/16 inch in diameter.
