The Frame Sheet Insert was designed specifically to fit the Lightfighter RAID, ATS RAID II and ATS Cobra Pack; but will also fit packs of the Eagle A-III size. It is made from a sheet of HDPE, bound with edge tape and with an aluminum stay in the middle to keep it rigid. 

The Frame Sheet is recommended for assault packs that carry heavy loads. If you have to really load your pack, the Frame Sheet will be an increase in performance for you.