I plan to buy a good full charging set for R12. I see 30lbs going for maybe 400 and in truth once I'm better equipped, pump, good charging set etc both my W123's are getting treated to re-built AC's. I know the systems are basically OK but leaky and hope to tear apart and fix at least one this summer. I didn't see the r12 hoses at HF but will look again. They are on-line too. I think I'll do that instead of the single charging hose. The car in question isn't an MB; the A/C still freezes you out after 16 years. I've never even removed the caps on the lines. There's a steady stream of bubbles when at full load so I wanted to add a couple of OZ's to keep everything working. My goal is to see the amount of bubbles drop a little, not go away completely.