One-Hand Trekker knives are large Swiss Army 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. There are many other variations of this knife, with different combinations of features (see below).

This model has also been called the One-Handed Trailmaster knife.

Trekker-- straight blade, no thumb release
One-Hand Trekker Non-Serrated-- non-serrated blade
One-Hand Trekker Black Blade-- black blade
One-Hand Trekker German Army-- olive shells with imprinted logo
One-Hand Trekker Camo-- camoflage pattern shells
One-Hand Trekker Camo Non-Serrated-- camoflage pattern shells, non-serrated blade

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