Here you go ...
Here's a pic of the page (180) out of GAHCo's catalog showing the "AN" specs for "Nut Clips".
GAHCo is about the premier seller of goods like this, and their catalog is one of the better resources for obscure fasteners ...
They used to be in Paso Robles, CA, but have since moved to Montana.
Their toll free phone number is (888) 247-2738. Very knowledgeable about their product line & always available to help.
HFS