Entrance To U.S with Business Visa

[immihelp]

Dear Sir or Madam,

I will go to United States of America with B1/B2 Visa for AIAA's 26 th Applied Aerodynamics Conference which will take place in Honolulu, Hawaii between 18 and 21 August 2008.

While completing the DS-156 form to take visa, I specified '15 August' as the date at which I intend to arrive at U.S.
But,will arriving U.S a few days before 15 August will be legal or do I have to arrive at U.S on 15 August specificially?

In addition,with B1/B2 Visa what is the maximum duration (in days ) to stay at U.S if purpose of my trip is to attend conference ?

Yours sincerely

[immihelp]

You can arrive any time during the validity of the visa stamp.

You can stay until the date stamped on I-94 form, at the port of entry.