Well in case of mechbox troubles, this can easily be fixed with standard replacements part matching the version of your mechbox (G36 is a version 3;so theoretically, most v3 parts made for tokyo marui aeg will be compatible). Ordering complete gearbox is also possible (and recommended if your gun is somewhat unusual internally like an MP40 for instance that possess a weird V3). The SRC V3 mechbox will last a while (it is build with good quality parts) - in case of troubles, you should call your local gun doc or ask for help BEFORE opening the mechbox (putting a mechbox back together is not easy - took me 3 hours the first time
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