how to Pass 1st Page (Comp.aspx) PK key value to Fk Key

Question

I have Two tables like 

 

create table Product

(

prodid varchar(50) primary key,

prodname varchar(50),

price int

)

 

create table Customer

(

custid varchar(50) primary key,

custname varchar(50),

custaddress varchar(50),

prodid varchar(50) foreign key references Product(prodid)

)

 

I have two pages like ProductDetails.aspx and

CustomerDetails.aspx

 So now i want to pass the PK value(Product Table) in Productdetails.aspx  to FK Key(Customer)CustomerDetails.aspx,

So please help me how to pass this task.....

 

 

Thanks in Advance