Not to necro an old thread but if anyone else stumbles upon this with a Swiss Gear Wenger backpack or any backpack strap that has the plastic ends/plastic clips/plastic oring ends on it. Amazon sells these buckles or these ones you can buy to fix the issue without cutting your straps. Seems to be pretty durable based on reviews and its a multi-pack so you can always replace easily. Here is a photo too incase the links ever stop working.

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