Inventor

GRZESEK ROBERT

US3 patents

Patents

3 patents

US7387559B2Jun 17, 2008

Toy vehicles and play sets with contactless identification

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US6614719B1Sep 2, 2003

Ultrasonic doppler effect speed measurement

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US6422911B1Jul 23, 2002

Toy device using through-the-body communication

MATTEL INC13 citations69