http://www.mysteryranch.com/packs/122/mystery-cinch.html
先引用一段原文，能看懂的兄弟就不必被我的烂翻译折磨了。
Packs and body armor – normally a painful combination. The packs shoulder pads slide off the armor and cut into your armpits causing bleeding, chafing and ultimately nerve damage. The pack can flop around and the chest strap on many packs can interfere and tangle with your tactical load.
The designers at Mystery Ranch have created a solution by adding a modular cinch strap – The Mystery Cinch – to the front of your IBA, MTV or other body armor.
Placing the Mystery Cinch just above the armor’s arm hole will route the shoulder straps of ANY pack down the front of your armor keeping the straps from cutting into your armpits.
The Mystery Cinch keeps your shoulder straps extended so that you can easily and quickly dump your load by pulling on a single button release.
The Mystery Cinch is compatible with any pack – CamelBak hydration, MOLLE, ILBE, ALICE rucks, and all Mystery Ranch packs of course!
原文大意是，同时用战术背心和背包是超级痛苦的。包的肩带会滑下来割伤自己（囧 老外真是细皮嫩肉啊），同时背包的胸袋会和背心上的东西打架而没法使用。
然后mystery的同志就搞出了这么个玩意，可以和任何背包及多数战术背心和谐相处。
有这玩意后有两好处
1 不打架了 舒服了
2 一按钮就可以丢盔弃甲
米国装备商为了骗取米军钱財，按照门上开两个洞，大猫走大洞，小猫走小洞的原理，为解决此问题，设计了：
1：专用MOLLE背包，贵；
2、新款的背带+MOLLE双用背包，背带拆卸或者折叠后用MOLLE 装在背心上，加倍的贵；
3、mystery 先生做的比较好，简单一条带子就保证了不滑落，但是售价有点贵。
但是米军中也有些不太傻的人，至少新款医疗包采取了一条普通织带，毫无衬垫的织带做肩带，解决了这个问题，反正有厚实的背心，肩带不需要衬垫。
花费——负数。