A loading unit for engagement with a surgical instrument, and including double pushers and double retention cavities. At least one double pusher includes a first body portion having a first upper surface configured to engage a portion of a first fastener, a second body portion having a second upper surface configured to engage a portion of a second fastener, and a bridge interconnecting the first body portion and the second body portion. Each of the first upper surface and the second upper surface defining an acute angle with respect to a longitudinal axis. At least one double retention cavity includes a first retention guiding surface configured to engage a proximal pusher guiding surface of the first body portion of the double pusher retained therein, and a second retention guiding surface configured to engage a distal pusher guiding surface of the first body portion of the double pusher retained therein.