Trading VIX options

which series, and underlying, has the 40p at $10.5?

 

dipping my toe in this vix thing, since everyone seem to be playing with them. trying out some trades:

1 VXX Sep11 42 Put $5.05
-1 VIX Sep11 42.5 Put $9.90

 

your put tracks Sep futures @31

 

What was the IVs of your put options?

 

How you do on trade? I lose $272.

 

http://www.elitetrader.com/vb/showthread.php?s=&postid=3289715#post3289715