One-Hand Trekker German Army knives are large knives (4 3/8" / 111mm) from Victorinox, that are similar to the smaller Hiker.

This variation of the Trekker features a serrated blade with a thumb release, so it can be opened with only one hand. It has olive-drab shells with a German Army insignia imprinted on one of them

There are many other variations of this knife, with different combinations of features (see below).

Trekker-- straight blade, no thumb release, black shells
One-Hand Trekker-- black shells
One-Hand Trekker Non-Serrated-- non-serrated blade, black shells
One-Hand Trekker Black Blade-- black blade, black shells
One-Hand Trekker Camo-- camoflage pattern shells
One-Hand Trekker Camo Non-Serrated-- non-serrated blade, camoflage pattern shells

Centurion-- no wood saw, no thumb release
Forester-- corkscrew instead of phillips screwdriver, no thumb release