In the interest preserving common sense, I would suggest that you don't need a torque wrench at all, which is not going to be anywhere near as precise as most people probably think it is. 25 inch pounds is about 8 pounds of force applied at the end of a three inch long wrench. You can do this by feel. We're not torquing engine blocks - just scope rings.
Show me a da-da-damn wrist calibrated to +/- 6% by ISO-6789, please.
Borka, Wiha and Proto units make the grade.
And it doesn't take the integral f(x) by separation of parts to figure what the right choice is.
Wiha #28508: 20 to 70in-lbs (+/- 6%)
• Tools Marked with Serial No. & Include Calibration Certificate
• Meets ASME B107.14m, EN ISO 6789, BS EN 26789
• Quality & Accuracy Guaranteed to 5000 Cycles
• Laser Calibrated & Scale Marked, Serialized for traceability
• Enclosed Mechanism Ideal for production controlled environments
• Secure Torque Setting, Requires torque adjustment tool
• Reverse Torque is 50% higher than indicated setting, easy removal
• Guaranteed accuracy to 5000 cycles or 1 year
I'm only editing in the spirit of common sense...
which cannot be purchased at Sears & Roebuck.