Aquastat Controller, Circulator Control and High Limit or Low Limit, Immersion Device for Limiting or Regulating Temperature of Liquids, 3/8" x 2 7/8" Copper Bulb, SPDT Contacts, Horizontal or Vertical Mounting, 100-240 Degree Operating Temperature Range, 1 1/2" Capillary Length, 5 Degree Fixed Differential Temperature, 1/2" Well Spud Size