Evenheat Kilns Type-K Thermocouple, 16 Gauge, 3" long from tip to block, includes three 1" x 5/16" cylindrical insulators and connection block as shown.
 
Suits Evenheat Models;
Kingpin
Fishbone
Artisan
 
Note; Your kiln may or may not have its original thermocouple, particularly if it were purchased used or replacements were made with incorrect or non-Evenheat parts.