DNA digestion time? - how long how many units (Aug/20/2002 )

I am always not sure how long to digest DNA
(i.e. Cosmid-DNA) and how many units of
enzyme i should use.
Therefore i would be thankful i some expierenced
guy could give me some tips!
Thanks! ???

You can find answers to all of your questions at New England Biolabs Web site http. Go to Restriction Enzyme->Biological Properties.