There is a flap so that you have access from the top. The flap is secured with buckles. Depending if commerical or mil spec, they may be fastex style buckles or threaded buckles.<br><br>The back side of the butt pack attaches to the belt and the Y or H harness attaches to the top corner of the butt pack.<br><br>Because the pack is located behind you, you cannot readily access the contents while wearing the LBE. The butt pack would stay attached to the belt and suspenders and you remove the entire LBE to access items in the butt pack. Typically you attach smaller pouches to the front of the belt or suspenders to carry items you would normally need while moving. The butt pack is for bulky items that are used infrequently.<br><br>Many people I know are changing from LBE and suspenders to a vest. The vests typically have a large pocket on the back for your camelback style hydration system. You can get vests either with a variety of pouches permanently attached or with web bands to accept ALICE pouches and you design your own layout.<br><br>The advantage is the weight is distributed over your entire body. The drawbacks include they can be hot, as you empty your camelback, the weight in the front pouches can force the vest down in front and up in back causing friction on your neck, the weight is being carried by your torso muscles instead of your pelvic and leg bones.<br><br>Some vests include "keepers" to help attach to a belt. Basically a narrow stip of webbing with snaps that act like belt loops on your pants. You attach the belt to the bottom of the vest and it helps to keep the vest in place and not ride up on you when bending over or during high activity periods.<br><br>