To me it only implies that Amazon recognizes there is manufacturer outlet as well. In this case, Pentair doesn't sell to the public so it's redirecting you to the Pentair general website, which sells replacement parts, but not the equipment.This clearly implies the product is being sold by and from the Pentair Store (not just that it is a Pentair product)
Although some manufacturers do sell through Amazon directly, I assume it's always through a 3rd party if I buy something there.