Why are the o-rings important? If they are worn out, compressed or have tiny nicks, they may allow air to leak into the line and you'll notice your ink lines have air bubbles or air gaps in them. This will cause ink starvation or drop outs which is not good for the heads. These are low cost items and cheap enough to for regular maintenance - changing them at every damper change or two.
Order by 5 pm pst for same day shipping from California