At first, I bought 2 SMA antennas from another guy. I thought they're pointless since my router supports TNC type only and I've no idea what SMA and TNC is.
Then I searched the forum and found MX510 selling this kind of SMA-to-TNC connectors. I decided to try and purchase.
Little did I know, it fits and works wonders now.

I must say MX510 is a good seller and fast delivery.
Recommended to buy from him!