The interface that connects an abrasive disc or polishing pad to the powered tool and supports it during rotation.
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Meaning and boundaries
A backing pad is not interchangeable solely by diameter; thread, attachment system, stiffness, balance, speed rating, condition, and accessory compatibility matter.
Why it matters in glass restoration
Poor centering, damage, mismatch, or excessive flex can change contact pressure, vibration, heat, and edge geometry.