When it’s necessary correct thermal variation of strain gauges, OTR suggests No stress strain gauge.

This device is composed by  a polycarbonate casing with nominal values IP6, NEMA 4X, UK508 where is lodged an an arch weldable strain gauge. The instrument is solidarity to a steel plate partialy free. Closed box dimension are (249.94x80.00x85)mm.

How is it used?            

It’s used like a reference box to correct the thermal variations due to difference between steel types and the normal drifts of the instrument.