How can I automatically send packing slips with fulfilment requests?

[Kimvegten]

Hi, 

I'd like to know if there is a way of automatically sending the packing slip with the fulfilment request that goes to our third-party supplier for free? At the moment we have to save the packing slip and send in a separate email, while the fulfilment request is automatically sent. 

Any suggestions greatly appreciated!

Thanks