```python
mapping = {
    "1500w psu": "unknown",
    "1500w receptacle": "unknown",
    "15a 110v breakers": "unknown",
    "15a outlets": "unknown",
    "15amp circuit 120v": "unknown",
    "15k cfm fan": "unknown",
    "15ohm resistors": "unknown",
    "15y board": "unknown",
    "16 5970s": "5970",
    "16 avalon chips": "unknown", # Avalon products are listed, but "avalon chips" is too vague.
    "16 awg pvc coated wire": "unknown",
    "16 bfl chip credits": "unknown", # BFL products are listed, but "chip credits" is not a hardware.
    "16 bit pic usb boot loader": "unknown",
    "16 bitfury chips": "unknown", # Bitfury products are listed, but "bitfury chips" is too vague.
    "16 board tower": "unknown",
    "16 chip board": "unknown",
    "16 chip credits": "unknown",
    "16 chips": "unknown",
    "16 credits": "unknown",
    "16 gauge (16awg) wire cables": "unknown",
    "16 gb blank cards": "unknown",
    "16 gb usd card": "unknown",
    "16 mh/s rig": "unknown",
    "16 mhz oszillator": "unknown",
    "16 pins cables": "unknown",
    "16 sticks": "unknown",
    "16-chip boards": "unknown",
    "160 chips": "unknown",
    "1600 evga watt psu": "unknown",
    "1600 w psu": "unknown",
    "1600 watt evga psu": "unknown",
    "1600 watt wine cooling unit": "unknown",
    "1600cfm fans": "unknown",
    "1600w evga": "unknown",
    "1600w power supplies": "unknown",
    "1600w power supply kits": "unknown",
    "1600w psu": "unknown",
    "1600w psu (1700w peak)": "unknown",
    "160mm fan": "unknown",
    "162 chip s7s": "unknown", # Closest match would be "antminer s7", but "162 chip s7s" is too vague.
    "16a2 boards": "unknown",
    "16awg copper wire": "unknown",
    "16awg pcie leads": "unknown",
    "16core opteron 8000 server": "unknown",
    "16gb flash-disk": "unknown",
    "16gb micro sd": "unknown",
    "16gb ram": "unknown",
    "16gb samsung cards": "unknown",
    "16mm cable": "unknown",
    "16nm rig": "unknown",
}
```