drupal commerce separate shipping for different products We have a drupalcommerce website through which we sale


iptv box 
qwerty key board


on adding first product it adds 15 dollars( base rate ) + 5 dollars per item in cart, so if we have 1 item in cart the shipping is 20 dollar but if we have 2 products the shipping will be 25 dollars and so on.

problem is, we want to setup separate shipping rate for qwerty key board if there is only a qwerty key board alone in cart the shipping must be 5 dollars.

I hope this can be done through shipping rules
You can add a shipping service dedicated for for qwerty key board and similar items and a shipping calculation that checks for a certain product in the cart. Use:
Event: Calculating a shipping rate
Condition: order contain a particular product. 
Action:Add a rate for a shipping service to an order and select the shipping service that is dedicated for qwerty key board and similar items. 

It may be easier for you to clone one of the existing shipping rate calculation and edit as needed.