sql 2008 - INSERT INTO

Wants to move(copy) data from different DATABASE

Server Name is :WIN-GIGA\SQLEXPRESS
Database names are
        1:RUNDATA
        2:BAKDATA
And in both the DATABASE ONE TABLE is common ie. Product
now i wants to copy the content of table from 'RUNDATA\Product'   TO BAKDATA\Product

what will be the query for vic versa Database...