Structural reinforcements

A structural reinforcement comprising:

• a carrier having an exterior surface and a length extending between a first end and a second end, the carrier including one or more sidewalls joined together to form one or more cavities, the carrier further including a cross-sectional shape roughly corresponding to the cross-sectional shape of interior walls of a hollow structural member;
• an activatable material having a uniform thickness placed over at least a portion of the carrier without the use of fasteners, the activatable material configured to expand upon application of heat and adhere to the interior walls of the hollow structural member to provide reinforcement to the same;
• one or more restricting features located on or integrated with the one or more sidewalls of the carrier, the one or more restricting features being configured to receive the activatable material and limit movement of the activatable material with respect to the carrier, wherein the one or more restricting features includes a slotted portion that extends along the length of the one or more carrier sidewalls, the slotted portion having an open area with a cross-sectional shape corresponding to a cross-sectional shape of the activatable material;
• and wherein the one or more restricting features include opposing walls that extend outwardly from the one or more carrier sidewalls and back towards one another to form the slotted portion;
• and
• one or more recesses extending along the length of the exterior surface of the carrier.