This cabinet is a factory-converted Gravitar game (#1809) - you can literally see the side art underneath the Black Widow art. The #1231 is taken from the game PCB.

Black Widow challenges you, the spider, to defend your web from mosquitos, beetles, hornets, and other insects. Use two joysticks to avoid or shoot enemies and bugs. Watch out for the grenade, rocket bug, thunder bug, spoiler, and collect the grubstakes for extra points! Skill Stepâ„¢, the Atari feature that allows players to start consecutive games at higher levels, offers players continual chalenge.
(source: Black Widow manual)

Dimensions: 71.74" x 25.25" x 31.59"
Weight: 307 lbs.

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