The 919-ADA from Adafruit is a RP-SMA Jack to SMA Plug RF Adapter.
This RF adapter bit is great for anyone doing RF work. Depending on the dev-board and antenna you have, you may be faced with either RP-SMA or SMA connectors. Unfortunately they are not compatible! This adapter solves the problem with a RP-SMA jack on one end and an SMA Plug on the other. We also have the opposite 'flavor' available
Check your cable, connector and antenna to verify whether you need this adapter, or the other flavor. In specific, look for the center contact, is it an 'innie' or an 'outie'? This adapter is likely best used for connecting an RP-SMA antenna to a board with an SMA connector.
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