The FILBE pack started being fielded by the Marines in approximately 2014. Since that time, several flaws have developed and have been addressed. The first one was that the first-generation frames could not support the loads that Marines were putting on them and they were cracking. This was addressed by the development of the 1606MC frame.
The next issue was the metal buckles on the shoulder straps frequently broke without warning or tore off of the shoulder straps completely. We corrected this by having local artisans remove that buckle and replace it with the proven side squeeze design that is all over the rest of the FILBE. This allows for easier field repair and parts sourcing as you can simply remove a buckle that is not being utilized elsewhere on the pack to perform emergency field repairs.
The next problem is really a logistical problem and not one with the packs, The lower halves (male end) of the metal shoulder harness buckles are incredibly difficult to obtain in quantities by the manufacturer of the shoulder straps and therefore they are even in short supply on active duty with as many as 20% of packs being issued without the straps and Marines being told to "make do" with 550 cord and other expedient solutions.
We had sourced buckles from another American company and had our local artisans construct lower shoulder harness straps from new webbing and buckles. We also went ahead and had them construct lower compression straps as well.
Our goal is to provide the most trouble free, useful, surplus ruck on the market and I firmly believe that we have succeeded in that.
Complete FILBE (UPGRADED & ASSEMBLED) | Authentic USMC Surplus for Outdoorsmen (otsurplus.com)