With fluorescent lights, the term "single-pin" refers to the single metallic contacts at each end of the fluorescent light tubes. Gas inside the tubes is ignited by a surge of spark that's provided by a ballast inside the light fixture. If the tubes flicker or won't come on at all, it's time to replace the ballast.
How do you replace a single pin fluorescent bulb?
https://www.youtube.com/watch?v=0AAUkFB3OH4
What is Fa8 socket?
Base Type: Fa8 Single Pin. Satco 80-1496 Single Pin Slimline Fa8 Base Replacement Fluorescent Plunger Socket - Primarily used to Update your 8' Fluorescent T12 or T8 fixture - Slide Shallow Base - Rated 660 Watts and 1000 Volts - Accepts up to 20 Gauge Solid or Tinned Leads.