The International Cessna^® 170 Association

I recently saw a 170B which had a small attachment to the above cabin fuel vent. It allegedly prevents (slows down) the not insignificant flow of fuel out through the vent if you decide to park with the oily side up...

Would someone please let me know if this is still available, from whom and, is it legal on 170As ?

Not that I plan on parking oily side up; you just never know when a wind gust will break the tie downs.

Thanks in Advance

There was a modification by service bulletin that Cessna developed to reduce fuel venting when performing wheel landings with heavy brake application which resulted in fuel venting onto the windshield. It consisted of a check-ball installation in the gooseneck vent.
It was subsequently rescinded because of icing and bug-ingestion problems. They should be removed and the gooseneck returned to the original status. (Fill the cotter-pin holes with silver-solder.)
Same thing applies to those modified with an anti-icing "weep" hole drilled in the aft surface of the vent tube.
The final fix was by AD note that specifies a vented fuel cap on the right tank.