Commandos are all about speed, especially when climbing down from a hovering helicopter (or a cliff or high building), or going up a rope to higher ground. There is an increasingly popular tool for this; a battery powered rope pulley. The technical term for this device is a Tactical Assault Ascender. One of the more popular models is the 17 kg/37.4 pound Swedish T1-16 ActSafe. On one charge, the ActSafe can lift up to 150 kg/330 pounds 400 meters, at a speed of up to 100 meters a minute (145 meters a minute coming down). The speed and distance can be programmed. When coming down, the battery is recharged. Otherwise it takes 45 minutes to recharge the battery. The ActSafe is waterproof (down to ten meters/31 feet underwater) and floats.
These devices have been featured in several movies, usually in the hands of professional thieves. This is something the manufacturers seek to avoid, and Tactical Assault Ascenders are only sold to government organizations. The last thing manufacturers want to see is Somali pirates using one to quickly board a merchant ship.