- Location under which Special Forces types can hide fishing line and a hook.
- Not required if you are Jewish (and a bloke obviously) although not sure where the Israeli Special Forces hide their fishing line!
- The 4-Skins. Skinhead 'Punk' band of the 80's much loved by the sadly mortal John Peel.
- The 4 Skins non SD abbreviation of a mythical cavalry unit which occasionally appeared on Situation maps marked by dozy clerks and watch keepers.