Honeywell 51201557-150 I/O Link ModuleDescription: The 51201557 150 module is an I O Link Extender Coupler designed to extend I O links in industrial automation systems. It requires two I O Link Extender cards and Fiber Optic Coupler modules at each end for Link A and Link B. This module supports one, two, or three fiber optic cables at the local card file and terminates a single optic cable at the remote IOP card file. Specifications: Type: Standard I O Link Extender Coupler