Amazon.com: YIOVVOM Connector DB9 RS232 D-SUB Male Serial Adapter 9-pin Port Adapter to Terminal Connector Signal Module with case(Male Connector, DB9 5+5 with case A) : Electronics
Office Depot
SENA PARANI-DB9FTB | Free Shipping
RS232 to RS422/RS485 Converter Adapter | TRENDnet - TRENDnet TI-S100
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Amazon.com: AAOTOKK DB9 Screw Terminal Block Adapter D-SUB 9-pin RS232 Male to 9+1 Pin/Way Female Serial Terminal Breakout Board Connector Signal Module with case (2Pcak/Male) : Electronics
DB9F-TO-TB/5pins Terminal Block to DB9 female adapter