美国BI公司全系列可调电阻，精密电阻，刻度盘；全系列型号有：78PR，67WR，67XR，72PR，25PR,89PR,7276，7286，44WR JR GR；

Standard Resistance Range, Ohms 10 to 2Meg
Standard Resistance Tolerance ±10% (<100 Ohms = ±20%)
Input Voltage, Maximum 200 Vdc or rms not to exceed power rating
Slider Current, Maximum 100mA or within rated power, whichever is less
Power Rating, Watts 0.75 at 85°C derating to 0 at 125°C
End Resistance, Maximum 2 Ohms
Actual Electrical Travel, Turns, Nominal 20
Dielectric Strength 1,000 Vrms
Insulation Resistance, Minimum 1,000 Megohms
Resolution Essentially infinite
Contact Resistance Variation, Maximum 1% or 1 Ohm, whichever is greater