The ATR was designed before the Salsa. We've learned from both. The longer blade of the ATR created some isues with strength, but they were sorted pretty easily. On the Salsa, we use a ball bearing / detent to keep the knife closed, because it is easier to build. On the ATR, we use the compression lock fitting into a carfefully milled section of the tang, to keep it closed (like the Gunting). It is more difficult to do. The rest of the refinements were minor shape changes, ramp angles, etc.
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