UPDATE: The XM-384 seems to be both a Mutt variant prototype along with the trailer. Leo found these photos that include the Mutt variant with its trailer. He found the photos on G503.
Steve spotted this unique trailer. According to the seller, this is a one-of-a-kind trailer. It was manufactured by Detroit Arsenal and built from aluminum.
“This is the trailer built for experimental Vechicle XM384 1957 (Detroit Arsenal). Its one of one. No others where ever built.”


























