This issue is rooted in Entity Framework rather than MVC x.
I ran into the same problem and printed out the fully qualified name of my model ("SupportContactSecurity"):
System.Data.Entity.DynamicProxies.SupportContactSecuri_4C68726A6CC129D0001F286F1E38612D8DEC28F26CA3D3884B53BCDF810D8E6A
DynamicProxies being the keyword there. Entity framework (by default) replaces your entities with these proxies so it can do change tracking at the context level (I think). If you want to turn this off, refer to this Stack Exchange question.