16.5" long prototype racer wind-up w/built-in key. Marx, 1937. Based on Marx's 1935 Rocket Racer, this prototype consists of two unused/unpainted top production racer halves that have been connected and assembled w/painted wooden wheels. Entire race car body has been hand-painted and toy features hand-made and painted double-driver metal figure that is counter-weighted so that when car is turned over, the correct driver pops up, ready for racing. Wheels are over-sized so that car can race on either side w/o "bottom" of car dragging on surface toy is operating on. Toy was later produced in 1939 as Marx's "Bouncing Benny - The New Safety Car" wind-up. Prototype has hand-painted "1358 - Erie-PA" text indicating it was produced at the Erie, PA. plant. In addition to Erie text, prototype also has hand-painted "4-8-37" date. Additional small hand-painted text at seam reads "Die Cost $2,480." Wind-up mechanism works and drivers figure function as designed. Prototype has all over crazing to paint on metal areas w/several scattered paint flakes revealing bare metal below. Cockpit area behind driver on both sides is totally bare in 1-3/8x2-3/8" area, likely as originally painted. Cockpits show wear w/trace oxidation. Tops of driver's heads have paint wear. Trace of oxidation to exposed metal on tail fins. Wind-up mechanism winds but slips. VG overall. Great design.