This ultra-comfortable premium head rest adjusts in four planes to insure a comfortable position for every rider. A closed-cell foam pad with a Lycra cover softly cradles your neck and absorbs shock but will not absorb moisture. This amazingly adaptable head rest will not interfere with the fenders, seat bag, commuter bag, rear rack, or panniers. It attaches easily by clamping to the ribs on the back of the seat frame. A couple of Allen wrenches (included) is all that is needed to mount this accessory. Compatible with all except TerraTrike versions 1.9 and older.