To: Steve B. us
"Steve; Go to a good hardware store and they will usually have two to three boxes of O rings. Each box having four to five drawers which slide out. When you remove a drawer and open it there is a page on the inside of the lid. This is a size match guide which you lay one of your O rings on to get an exact match to the O ring you have. Good Luck. (Hope that True Sword will post this or get the info. to you. )"