Rolling tonneau cover

1. A tonneau cover assembly that selectively covers a truck bed of a truck, the tonneau cover assembly comprising:

a cover; and

a longitudinally extending rail located adjacent a sidewall of the truck bed;

wherein the longitudinally extending rail includes an attachment member;

wherein at least a portion of the attachment member has a planar body;

wherein the attachment member extends longitudinally with the longitudinally extending rail and the at least a portion of the attachment member is located over a portion of the truck bed;

wherein the at least a portion of the attachment member is inclined with respect to a top surface of the sidewall;

wherein the cover includes a stiffener located on an underside of the cover and adjacent the attachment member of the longitudinally extending rail;

wherein the stiffener has a body that is more rigid than the cover;

wherein the stiffener includes a depending rib extending from the stiffener toward the attachment member; and

wherein a tip of the depending rib located distal from the stiffener engages a surface of the attachment member to space apart a portion of the cover from the attachment member.

2. The tonneau cover assembly of claim 1 , wherein the cover is made of a flexible material.

3. The tonneau cover assembly of claim 1 , wherein the attachment member includes an attachment slot sized and configured to receive a portion of a hook and loop fastener.

4. The tonneau cover assembly of claim 1 , wherein the stiffener is composed of a material selected from the group consisting of at least one of an extruded rubber and a thermoplastic elastomer.

5. The tonneau cover assembly of claim 1 , wherein the stiffener and rib extend longitudinally adjacent the attachment member.

6. The tonneau cover assembly of claim 1 , wherein the rib separates a portion of the stiffener from a portion of the attachment member.

7. The tonneau cover assembly of claim 1 , wherein the rail includes a clamp bracket that extends downwardly with respect to the attachment member and located adjacent the sidewall.

8. A tonneau cover assembly that selectively covers a truck bed of a truck, the tonneau cover assembly comprising:

a cover; and

a longitudinally extending rail located adjacent a sidewall of the truck bed;

wherein the longitudinally extending rail includes an attachment member;

wherein at least a portion of the attachment member has a planar body;

wherein the attachment member extends longitudinally along with the rail and the at least a portion of the attachment member is located over a portion of the bed;

wherein the cover includes a stiffener located adjacent the attachment member of the longitudinally extending rail;

wherein the stiffener includes a rib extending from the stiffener; and

wherein the rib includes a tip located distal from the stiffener such that the tip contacts a surface of the attachment member.

9. The tonneau cover assembly of claim 8 , wherein the at least a portion of the attachment member is inclined with respect to a top surface the sidewall.

10. The tonneau cover assembly of claim 8 , wherein the stiffener is located on an underside of the cover.

11. The tonneau cover assembly of claim 8 , wherein the stiffener has a body that is more rigid than the cover.

12. The tonneau cover assembly of claim 8 , wherein the rib extends downwardly from the stiffener.

13. The tonneau cover assembly of claim 8 , wherein the rib separates a portion of the stiffener from the attachment member.

14. A tonneau cover assembly that selectively covers a truck bed of a truck, the tonneau cover assembly comprising:

a cover;

wherein a portion of the cover includes a longitudinally extending stiffener;

wherein the longitudinally extending stiffener includes a rib extending from the longitudinally extending stiffener; and

wherein the rib includes a tip located distal from the stiffener such that the tip contacts a surface of a longitudinally extending rail.

15. The tonneau cover assembly of claim 14 , wherein the longitudinally extending rail includes an attachment member, wherein at least a portion of the attachment member has a planar body.

16. The tonneau cover assembly of claim 15 , wherein the attachment member extends longitudinally with the rail and the at least a portion of the attachment member is located over a portion of the truck bed.

17. The tonneau cover assembly of claim 16 , wherein the stiffener is located on an underside surface of the cover, located adjacent the attachment member of the longitudinally extending rail, and the rib separates a portion of the stiffener from a portion of the attachment member.

18. A tonneau cover assembly that selectively covers a truck bed of a truck, the tonneau cover assembly comprising:

a cover; and

a longitudinally extending rail located adjacent a sidewall of the truck bed;

wherein the longitudinally extending rail includes an attachment member;

wherein at least a portion of the attachment member has a planar body;

wherein the attachment member extends longitudinally along the rail;

wherein the at least a portion of the attachment member is inclined with respect to a top surface the sidewall;

wherein the cover includes a stiffener located on an underside of the cover and adjacent the attachment member of the longitudinally extending rail:

wherein the stiffener includes a rib that depends from the stiffener; and

wherein the rib includes a tip located distal from the stiffener such that the tip contacts a surface of the longitudinally extending rail.

19. The tonneau cover assembly of claim 18 , wherein the stiffener has a body that is more rigid than the cover.