The 66951-006LF is a vertical card connector designed for single-row PCB interconnection with 100-pin center spacing at 2.54 mm intervals. This connector features a 0.025"/0.64 mm square mating pin design centered within 0.015"/0.38 mm diameter tolerance, with suggested mating pin length of 0.210" ± 0.020" (5.33 ± 0.51 mm). The connector is manufactured with 100% tin plating in the interface and is rated to withstand 260°C peak temperature for 20 seconds in wave solder, infrared, or vapor phase solder processes. The "LF" suffix designation indicates a lead-free option compliant with European Union directives and other country regulations. This connector is commonly used in industrial and commercial PCB applications requiring reliable vertical card-to-board connections with standard metric spacing.