How to make my client application recognize an object from my web service as a type that it already knows?

So, I have a web service that returns a non-standard type

public List<MyNS.Product> GetProducts(string filter)
{
    ...
}

MyNS.Productdefined in another assembly. The client application refers to the same assembly. When I add a service link to my client application, the return type is MyServiceReference.Product.

var client = new MyServiceReference.dataSoapClient();
var products = client.GetProducts("derp");
// products type is MyServiceReference.Product[]

How do I get my client application to recognize that the returned type object MyServiceReference.Productis actually a type MyNS.Productthat it already knows about? (the list for the array is not big, just type T)

The web service is a regular asmx as part of the website. I am doing an “add service link” to add a service to my client’s project in visual studio.

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