The Victorinox Caddy Plus Swiss Army knife is a very compact pocket knife designed for golfers.

This is a retired model that is sometimes available in new or used condition. It's the only variation of the Caddy knife that includes a pen.

Caddy-- no bottle opener, toothpick instead of pen (retired)
Caddy Rover-- no scissors, toothpick instead of pen (retired)

Golfer-- adds corkscrew, hook, toothpick (retired)
GolfTool-- no pen, adds tee punch with nail file, toothpick and ball marker

Executive Golf Pro-- no scissors or pen, adds ball marker, nail file, score counter

The standard Caddy Plus knife is only available in red shells.

Some advertising knives come in other colors, usually with the name of a golf course or a golf tournament printed on them.