TE Connectivity 2.50mm Economy Interconnection (EI) PCB Header Connectors EI Series (Economy Interconnection) 2.5 mm partially shrouded PCB pin headers with a compact design ideal for making high density wire to board connections. These EI Series headers have a polarized locking latch that ensures a secure connection is made to the mating receptacle connector. The housings are made from UL 94V-0 rated 6/6 nylon and are colour coded. These EI Series 2.5 mm PCB pin headers are available in vertical or right angle configurations and with gold or tin plated contacts