M.2 type of Wi-Fi Modules
M.2 is formerly known as the Next Generation Form Factor (NGFF), this is newer and smaller form factor that use the PCI Express interface. This form factor was introduced and widely applied on thin notebook computers, and tablet computers, to create a thinner, powerful unit. 
WNFQ-258ACN(BT)
802.11ac/a/b/g/n WiFi + Bluetooth M.2 Module, Qualcomm Atheros QCA6174A-5, 2T2R
- Standard: 802.11ac/a/b/g/n, Bluetooth V4.1,V4.0 LE, V3.0+HS, V2.1+EDR
- Host interface: M.2 Card (WLAN: PCIe ; Bluetooth:USB2.0)
- Chipset: Qualcomm Atheros QCA6174A-5
- Antenna: 2 x IPEX MHF4 connector, 2T2R
- Supports for BT & WLAN Co-existence
- Supports 20/40MHz at 2.4GHz and supports 20/40/80MHz at 5GHz
- Supports MU-MIMO
WNSQ-261ACN(BT)
802.11ac/a/b/g/n M.2 LGA Type 1216 Module, Qualcomm Atheros QCA6174A-5, 2T2R
- Chipset: Qualcomm Atheros QCA6174A-5
- Antenna: 2xIPEX MHF4 connectors, 2T2R
- From Factor: M.2 LGA Type 1216
- Interface: PCIe: WLAN; USB: Bluetooth
- Output Power up to 18dBm
- Support: Windows 7/8.1/10
WNFT-234ACN(BT)
802.11ac/a/b/g/n WiFi + Bluetooth M.2 Module, Realtek RTL8822BE, 2T2R
- Support Multiple Drivers (Android / Windows / Linux)
- Antenna: 2xIPEX MHF4 connector (Support WiFi/BT co-existence)
- From Factor: M.2 2230, 2T2R
- BT transmission Speed including 1M, 2M and 3Mbps EDR
- Output Power up to 16dBm
- Support MU-MIMO