A clamping mechanism for a surgical instrument, comprising: an upper elongated member having a distal portion and a proximal portion; and a lower elongated member having a distal portion and a proximal portion; the upper and lower elongated members being configured to engage each other at a first interlock and a second interlock, the first interlock distal of the second interlock, whereby the clamping mechanism is movable between a first configuration, a second configuration, and a third configuration, wherein, in the first configuration, the upper and lower elongated members are approximated towards each other and the first and second interlocks are not engaged, wherein, in the second configuration, the distal portion of the upper and lower elongated members are moved away from each other, the first interlock is engaged, and the second interlock is not engaged, and wherein, in the third configuration, the distal portions of the upper and lower elongated members are moved away from each other relatively, the proximal portions of the upper and lower elongated members are moved away from each other relatively, the first interlock is engaged, and the second interlock is engaged, wherein: the upper elongated member comprises a first I-beam portion configured to engage one of an anvil or an upper jaw of the surgical instrument; and the lower elongated member comprises a second I-beam portion configured to engage one of a staple housing or a lower jaw of the surgical instrument, wherein: the upper elongated member comprises a first flex region between the first interlock and the second interlock, the first flex region configured to bend to allow the distal portion of the upper elongated member to rotate relative to the proximal portion of the upper elongated member, wherein: the distal portion of one of the upper elongated member or the lower elongated member comprises a cutting mechanism, and wherein: each of the first interlock and the second interlock comprises a flange engagement between the upper and lower elongated members to limit expansion of the upper and lower elongated members to a predetermined distance. an upper elongated member having a distal portion and a proximal portion; and a lower elongated member having a distal portion and a proximal portion; the upper and lower elongated members being configured to engage each other at a first interlock and a second interlock, the first interlock distal of the second interlock, whereby the clamping mechanism is movable between a first configuration, a second configuration, and a third configuration, wherein, in the first configuration, the upper and lower elongated members are approximated towards each other and the first and second interlocks are not engaged, wherein, in the second configuration, the distal portion of the upper and lower elongated members are moved away from each other, the first interlock is engaged, and the second interlock is not engaged, and wherein, in the third configuration, the distal portions of the upper and lower elongated members are moved away from each other relatively, the proximal portions of the upper and lower elongated members are moved away from each other relatively, the first interlock is engaged, and the second interlock is engaged, wherein: wherein, in the first configuration, the upper and lower elongated members are approximated towards each other and the first and second interlocks are not engaged, wherein, in the second configuration, the distal portion of the upper and lower elongated members are moved away from each other, the first interlock is engaged, and the second interlock is not engaged, and wherein, in the third configuration, the distal portions of the upper and lower elongated members are moved away from each other relatively, the proximal portions of the upper and lower elongated members are moved away from each other relatively, the first interlock is engaged, and the second interlock is engaged, wherein: the upper elongated member comprises a first I-beam portion configured to engage one of an anvil or an upper jaw of the surgical instrument; and the lower elongated member comprises a second I-beam portion configured to engage one of a staple housing or a lower jaw of the surgical instrument, wherein: the upper elongated member comprises a first flex region between the first interlock and the second interlock, the first flex region configured to bend to allow the distal portion of the upper elongated member to rotate relative to the proximal portion of the upper elongated member, wherein: the distal portion of one of the upper elongated member or the lower elongated member comprises a cutting mechanism, and wherein: each of the first interlock and the second interlock comprises a flange engagement between the upper and lower elongated members to limit expansion of the upper and lower elongated members to a predetermined distance.