Magnetic Head Series w/Normal or Long-Lifetime Technology Support, ... -, 2-, 3-track read head series used in POS (point of sales), magnetic card readers/writers, credit/debit cards ... 2M-1RXXXX-1 series (1-track read head series): Outline dimensions: ... 8.0mm to 9.7mm2M-3RXXXX-1 series (3-track read head series): Outline dimensions: 11.8mm x 11. ...