new to fly fishing/line help
I recently purchased a used Ross Colorado 3 reel off of Ebay, it's in great condition and has scientific mastery line on it (or the seller told me so). I am somewhat confused with the end of the line, however. What is the loop at the end and if it breaks how do you fix it/replace it? It almost looks like mesh and is held on with a red rubber sleeve. I have tried the 3m website, but no luck. Could someone help out a rookie wanting to learn.