Here's my partial listing of discontinued Collegiate dressage saddle model names and the model numbers that correspond to them. You might want to squirrel this away. Feel free to add, all you savers of obsolete Miller's Saddlery catalogs. The "RD" stamped on the Collegiate saddles and/or painted on the metal tag refers to the manufacturer, Ruiz Diaz. That company makes Collegiate saddles, Klimke, Pessoa, and Whitman's Avante line as well. Possibly some lesser known Argentine brands, too. ART or R with the number is regular medium tree width. I'm guessing that "W" is wide. Anyone know? Anyone? Anyone?? "Classic" (copy of Crosby Freestyle? or Prix St. George?) 6528 Baron (copy Kieffer Wein) 6507 Jessica (copy Passier Nicole? I forget) 6542 (there were a couple iterations of the Jessica ) Klimke 6502 Mentor 6504 Sr. Event AP 6529 Lisbon (close contact model) number? – I don’t have it From Miller's 1996 catalog: Model 6548 is the Collegiate "Champion" Dressage saddle. "Miller's celebrates the Medal-winning legacy of US Olympians with our 1996 Commemorative Collection of new show jumping, dressage, and event saddles. Each specially created limited-edition model proudly displays the USET logo and is distinctively embossed with the USA/5-ring logo individually numbered and personally registered for lasting value...." Here is the saddle description: "Exceptional feel and security. With deep seat, narrow, contoured, close contact flaps, long billets, traditional stuffed panels".