MILLIVOLT DIRECT CURRENT ELECTRIC THERMOSTATS (RX SERIES) 200-400F, 24" Capillary, 3/8" X 5-5/8" Nickel Bulb, Factory Model RX-10. SPST - Break on temperature rise. Hermetically sealed reed switch provides durability and accuracy in the harshest environments. Rated for .67 amps at 5 VDC. Maximum ambient temperature 230°F (110°C). Maximum differential is 8°F. Precise and proven snap action mechanism. Screw type terminals ensure electrical integrity. All RX models listed by UL, CSA, IEC, and AGA. Stem length 13/16"Replaces VULCAN 411506-13, Robertshaw KX-396, Robertshaw RX-2