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"Whirlwind" - black galvanized, high gloss, low magnetic
Pinball 27mm (1 1/16")
Also for Pinballs using magnets, e.g.:
Apollo 13
Centaur
Cirqus Voltaire
Starship Troopers
The Shadow
...
The balls are not suitable for pinball machines with e.g. metal plates over the target banks (see GoldenEye). If the ball rebounds with great force against a metal edge, the surface might be damaged.