No cotter keys required. No taping. The clean design prevents dislodging accidentally or fouling lines. Types "M" is considered deluxe styling and are positive locking. These also allow for one-hand release, but with these just push the button, then pull. There's no faster operating locking pin or safer pin.
The unique Ball-Loc action means it cannot dislodge accidentally, even under severe tension. These pins are non-corrosive, aircraft quality 316 stainless steel. "Grip Length" is the distance from the shoulder to the locking ball bearings.