This model is no longer in production. It is recent enough that we don't consider it a collector's item, so we sell it for a few bucks less than the price of the standard Altimeter. This might be a good choice if you really don't need the pen, pin or tweezers, or if you think it will become a collector's item in the future.

Altimeter-- adds tweezers and pen
Altimeter Plus Original-- adds wood saw
Explorer-- no altimeter, adds magnifier and phillips screwdriver
Voyager-- replaces altimeter with digital clock

The Altimeter knife is only available in ruby translucent shells.