The outside is covered with a rubber coating for durability, and gives you that "Slap" that makes you react naturally to the strike!
There is 1/2" of high density foam at the tips for aggressive thrusting.
Both the THICK STX and THIN STX have a 6" handle that is more like gripping a real stick.
The Hollow core Stx have a slight flex that allows them to whack you pretty good, without blunt trauma injury. The 21" Stick might be the "perfect" padded weapon. they feel great, and are highly recommended for children in combat mode!
The Reinforced Hickory Stx add Rigidity to the Sof-Stx and feel more like a real stick.
The Nylon core sticks are for those folks that like some heft...they do hit harder.