John E. Dettmann

Person

  • Madison, WI, US

Patents Grantslast 30 patents

  • Information Patent Grant

    Football training apparatus

    • Patent number 6,761,650
    • Issue date Jul 13, 2004
    • Helgesen Industries, Inc.
    • John E. Dettmann
    • A63 - SPORTS GAMES AMUSEMENTS