Plumbing question: shutoff valve in kitchen - reuse existing parts?

I managed to remove the existing shutoff valve from underneath my kitchen sink. Now the question is do I reuse the part that looks like a ring or collar? If I should replace the "ring" with the new one that came with my new shutoff valve, how do I remove the old one? It appears to be buried way back somewhere in the existing nut.

Answers:
Assuming it's a compression fitting you'll have to use the existing one. To remove it you will have to cut the tubing it fits on and you don't want to do that.

Other answers:
It is always a good idea to start fresh with new parts! Go to your local home improvement store and get new parts the cost is not much. A lot better than doing it over, time is money.
It is always a good idea to start fresh with new parts! Go to your local home improvement store and get new parts the cost is not much. A lot better than doing it over, time is money.
If it's a compression fitting you should use the existing one. To remove it you will have to cut the tubing it fits on and you probably don't want to do that. Try reusing what is there and keep an eye on it for a while. Remember, it only needs to be water tight, not muscular tight. There is a difference.
Don't listen to these dudes. I f you try to replace the whole thing, you'll be opening up a can of worms unless you're a plumber. Use the existing ring and nut that's still on the pipe. When you put the new part on, just wrap Teflon tape around the threads of new piece. Wrap in a clockwise direction 3-4 revolutions around the threads. To ensure there are no leaks, I usually add a light coat of joint compound on top of the Teflon tape in a clockwise direction without getting it inside the part. Both sealants are sold at any home improvement center like Lowe's or Home Depot. Just make sure you tighten the existing nut onto the new part's threads real snug. When you turn the main water supply back on, check for leaks after running the water for a minute and then shutting it off. Make sure the nut that's closest to the handle (packing nut) doesn't drip. If it does, tighten that nut clockwise, but don't crank on it too hard. You may want to put another wrench on the pipe's nut when you tighten the packing nut to ensure the valve doesn't move. I've done many of these and have never had one leak on me. But of course, I have skiiiiilllllllz.
  • Why do people hang shoes up thier power line for?
  • Can I use "weed and feed" and something to kill bugs at the same time?
  • I Got Paint Thinner on the couch. what do I do?
  • Where can I get training to become plumber?
  • oil fired hot water heater not pumping oil , why?
  • what is the shallowest pitch for metal roofing?
  • what's the best mole trap?
  • What is the cable called that hooks up to the VCR and the TV? The screw on one?
  • What is wrong near our wash tool?