The THOMAS & BETTS RC610 terminal block markers are pre-printed with horizontal even/odd numbering from 1 to 20, simplifying identification and organization of terminal blocks. Constructed from durable polyamide, these markers are designed for use with SNA double deck terminal blocks. They enhance the clarity and efficiency of electrical installations, reducing errors and improving maintenance. These markers are a crucial accessory for maintaining well-organized and easily identifiable electrical panels and systems.