The rampant popularity of the cassette-playing Soundwave and Blaster carried on from the early Generation 1 into 1986. However, to that point, all the associated Mini-Cassettes had been Decepticons. Finally, the Autobots received their own Mini-Cassettes, such as Steeljaw, who lacks a humanoid mode, instead having a robotic lion mode.

US Patent for G1 Steeljaw


Steeljaw was designed exclusively for Transformers by Takashi Matsuda. Unlike the previous cassettes, he had no roots in Takara’s Microchange. His design takes clear cues from that of Ravage, however. Early shots from a Toy Fair catalog show a completely different, and far less realistic, cassette front decoration. Steeljaw’s US Patent, titled Reconfigurable¬†toy¬†cassette (aka Transformers G1 Steeljaw) was filed on March 15, 1985 (U.S. Patent No. USD295542 S).


Steeljaw’s alternate mode is a yellow Olympus Type IV “Metal” MC60 Microcassette, in a real-life scale. The front of the cassette is detailed with stickers that fairly realistically depict the printing on a Microcassette, including the edges of the two tape reels as seen through a window, with a playback time gauge included below. Stickers were also used to represent the holes for the cassette player’s pins, but actual holes (complete with a molded-in “tooth” look) are present for the player’s drive spindles. The back of the cassette is only decorated with molded-in robot details. Steeljaw transforms by extending his well-articulated die-cast metal legs from the bottom of the cassette, rotating a tail down from the back, extending the body, and rotating the head out from the side of the tape. In lion mode, he has gold-chromed eyes, as well as articulated hips, knees, and paws. He is armed with two large chrome guns with vertically prodtruding wings, that plug into the hole through his rear body.

Collector Notes

Despite his small size and fine detail, large pins connecting his hips and shoulders, as well as riveted die-cast metal legs make Steeljaw remarkably sturdy. However, his gold eyes are vacuum-metalized rather than stickered, making them somewhat prone to wear. Furthermore, his stickered cassette face is divided into very small segments to accommodate the moving parts, leaving the tiny stickers prone to wear and peeling.


Steeljaw was available in two primary variants: either including silver vacuum-metalized weapons, or gold vacuum-metalized weapons.


Steeljaw was only available in Hasbro’s territories packed with Rewind (whose weapon variant always matched that of Steeljaw). The Steeljaw & Rewind 2-pack was available again in 1987. In Japan, Steeljaw was available in 1986 single-packed with gold weapons. In 1987, he was available in Japan either single-packed, or packed in with Twincast.This version featured paler yellow plastic on the head, tail, hips and feet. Steeljaw was reissued in Japan in 2006 as part of The Transformers Collection, packed with Broadcast, and including gold weapons. He was reissued again in Encore in 2009, as part of The Great Cassette Operation vol. 2 with Ratbat, Ramhorn, and Slugfest. This version had the pale yellow highlights, and gold weapons. This version also uses tampographed tape face details instead of stickers, and bright silver finish on the die-cast legs. Steeljaw was finally reissued in the US with the San Diego Comic-Con Universe 2 Blaster. This version used the same yellow plastic throughout, had gold weapons, and had tampographed details.

Redecos & Retools

Steeljaw’s mold was redecoed to create Nightstalker, who was packed with Encore Twincast.