Fringe Bleach either Masterblend or
Chemspec is a strong oxidizer but rather than using sodium as the ionic bonding agent, it utilizes Potassium. So instead of say Sodium percarboante or Sodium Hypochlorite, RX uses Potatsium Peroxymonsulfate and Potasium carbonate.
The potasium is a bit more reactive than the sodium but in this case, the oxidizing reaction that occurs is much milder on the fabric than sodium percabonate can be.
However, its still a strong oxidizer and should only be used on pure white fabrics.
BTW. if you are simply trying to correct browning, Glaciel acetic acid works very well. Masterblends Master Rinse, Chemspec's
All Fiber Rinse are a few examples..
Using Fringe bleach will cause fringe deteriorate after repeated bleachings.