Square D A3.95 Thermal Unit Brand: Square D. Part Number: A3.95. Square D Thermal Unit, Melting Alloy, 600 V AC, 2.67 to 3.48 A Full Load, Class 20/Standard Trip, 1.8 in L x 2.6 in W x 3.6 in H, Plug-In Mount, 40 deg C. Additional Description: SQD -A3.95 THERMAL UNIT. Catalog Description: Thermal Unit, Type S, Type A, melting alloy, Class 20..