Make checkboxes check if they exist in a table

Hi
 
I'm trying to make checkboxes check if they exist in a table.
 
What I'm initially trying to do is to list the values is a table e.g. product types, and then if a product has those types assigned to it mark the check box as checked.  e.g.
 
Products Table
Prod No   Prod Name
1             Silver Bag
2             Black Bag
3             Red Hat
 
Product_Types Table
Prod_Type_No    Prod_Type_Name
1                         Bag
2              & ...