Felting Needles, not your usual arts & crafts tool, command respect and safety and are specific to dry felting.  As you can see in the picture they have very sharp notches along the shaft of the needed, which create felt without the help of water. It is quite an old technique (3500 B.C in fact) where the needles grab the fibers from the top fabric or layer and tangle them with the fibers of the bottom fabric.  These needles are so cool and fun to use.  I recommend keeping a bandage handy - I speak from experience.