Puzzle

1. A puzzle kit comprising:

a three dimensional substrate having an outer surface; and

a plurality of puzzle pieces that cannot interlock with each other, each puzzle piece having a first surface and an opposite second surface and a thickness defined between the first and second surfaces;

each puzzle piece comprising first attachment means and the outer surface of the substrate defining a plurality of complementary second attachment means, such that the first attachment means and the second attachment means attach each puzzle piece to the outer surface;

wherein the first and second attachment means are configured to magnetically attach at least one puzzle piece to the outer surface, the puzzle piece having first attachment means comprising a projection extending from the second surface of the puzzle piece and the outer surface having complementary second attachment means comprising a hole to partly receive the projection, wherein the projection has a length and the hole that receives the projection has a depth that is 90% or less of the length of the projection.

2. A puzzle comprising:

a three dimensional substrate having an outer surface; and

a plurality of puzzle pieces that cannot interlock with each other, each puzzle piece having a first surface and an opposite second surface and a thickness defined between the first and second surfaces;

each puzzle piece comprising first attachment means and the outer surface of the substrate defining a plurality of complementary second attachment means, such that the first attachment means and the second attachment means attach each puzzle piece to the outer surface;

wherein the first and second attachment means magnetically attach at least one puzzle piece to the outer surface, the puzzle piece having first attachment means comprising a projection extending from the second surface of the puzzle piece and the outer surface having complementary second attachment means comprising a hole that partly receives the projection thereby forming a puzzle layer spaced from the outer surface, wherein the projection has a length and the hole that receives the projection has a depth that is 90% or less of the length of the projection.

3. The kit according to claim 1 , wherein the outer surface is helmet-shaped.

4. The kit according to claim 1 , wherein the depth of the hole corresponds to 50 to 80% of the length of the projection.

5. The kit according to claim 1 , wherein the projection has a hexagonal cross section.

6. The kit according to claim 1 , wherein at least one puzzle piece has a first surface that is hexagonal.

7. The kit according to claim 1 , wherein the plurality of puzzle pieces comprise hexagonal and pentagonal puzzle pieces.

8. The kit according to claim 1 , wherein the projection has a maximum diameter and the first surface has a maximum diameter that is at least two times greater than the maximum diameter of the projection.

9. The kit according to claim 1 , wherein one or more puzzle pieces has a convex surface and an opposing concave surface.

10. The kit according to claim 1 , wherein the plurality of puzzle pieces form a puzzle layer that extends over 50% or more of the outer surface of the substrate.

11. The kit according to claim 1 , wherein the substrate is hollow.

12. The kit according to claim 1 , wherein the plurality of puzzle pieces form a puzzle layer having an opening therein.

13. The kit according to claim 1 , additionally comprising one or more of: a visor, a sun shield, a face guard, a vent, or an aerodynamic fin.

14. The kit according to claim 1 , additionally comprising a light source or a stand.