In hot-rolling mills, the gap between work rolls must be measured continuously to maintain strip thickness within microns—yet the environment is saturated with scale, steam, and vibration that would destroy wired sensors. This wireless measurement probe sits directly on the roll stand, transmitting real-time gap data without physical connections. Its role is to replace the fragile cable that once linked the sensor to the control system, eliminating the most frequent point of failure in the thickness control loop. Mounted on the roll housing or chock, the probe tracks the exact distance between the rolls as they deform under load. Operators rely on this signal to adjust hydraulic capsules or screw-downs, ensuring uniform gauge across the entire coil. Because it operates without a tether, the probe can be installed in tight spaces where cable routing was impossible, such as on reversing stands or in narrow-width mills. The absence of cables also removes a tripping hazard and reduces maintenance stops for cable replacement, typically required every few weeks in high-scale areas. While primarily used in hot-strip and plate mills, the same probe is also fitted in cold-rolling lines where oil mist and high speeds demand a contactless solution. Here, it monitors roll gap during threading and speed-up phases, preventing strip breaks that halt production.