# Mach I (SLIDE RULETTE)

The Mach I is an arithmetic calculator with algebraic logic. It has 6 functions, 19 keys, and a VFD (vacuum fluorescent) display. The power source is 4xAA.
**Note:** Unisonic 1212

## Facts at a glance:

Feature | Value |
---|---|

Type | Arithmetic |

Functions | 6 |

Keys | 19 |

Logic | Algebraic |

Display type | VFD |

Length | 133mm |

Width | 83mm |

Power Source | 4xAA |

Year introduced | 1972 |

## Replacements:

If you have a Mach I that is no longer working, you can first try replacing the 4xAA batteries. If that doesn't solve the problem, then you can consider replacing the calculator with a modern equivalent.

We suggest the following current models as possible replacements: