These cells have a unique humidity resistant protective coating assures long term stability even under harsh environment and extreme temperatures. Mounting screws are 1/4-20 UNC(coarse) with 3/4" spacing on both top and bottom. 2 mv/v, 0.02% total error, 9 ft 6 cond cable 1040: 415/350 ohm, anodized aluminum. 1140: 380/350 ohm, stainless steel. 1040: NTEP 89-075 S III 5,000 div