Serial adapters / converters are extras from a power backup upgrade across dozens of stores. In original plastic bags from APC (American Power Conversion). Should work very well in converting / adapting any serial port connection, unlike the cheap clones.Authentic Schneider Electric / APC product, guaranteed. Buy more and save. I heavily discount quantity purchases! Also, expedited shipments (USPS Priority Mail) are a flat $10 cost, regardless of quantity -- I'll pay the difference regardless of # you buy. (e.g. buy 50 and fast shipping is $0.25/each)