MS8515gs:

Support 2.4G frequency
Protocol standards: IEEE 802.11n, IEE 802.11g, IEE 802.11b
Encryption: WPA-PSK/WPA2-PSK; TKIP/AES; 64/128 bit WEP encryption
Operating system support: Window 2000/XP/Vista/Win7/Linux/Mac
Interface: USB
Antenna: External detachable Antenna
Weight: 39g
Size: 9 x 6.5 x 1.6cm(L x W x T)

MS1537:

Mini size and light weight

External detachable antenna

Protocol standards: IEEE 802.11n, IEE 802.11g, IEE 802.11b

Antenna Type: 6dBi Omni-antenna

Interface: USB 2.0 Hi-speed connector

Frequency: 2.4-2.4835GHz

Modulation type: DBPSK, DQPSK, CCK, OFDM

Encryption: WPA/WPA2; TKIP/AES; 64/128 bit WEP encryption; WPS

Operating system support: Window XP/Vista/Win7/Linux/Mac

Weight: 27g(with antenna)

Size: 4.5 x 1.2 x 0.8cm(L x W x T)

Antenna length: 19.8cm

N8531:

Standards: IEEE 802.11n, IEEE802.11g, IEEE802.11b

Transmission mode: DSSS

Encryption: WPA; TKIP/AES; 64/128 bit WEP encryption; WPS

Operating system support: Window XP/Vista/Win7/Linux/Mac

Interface: USB

Weight: 1g

Color: Black

Size: 2 x 1.4 x 0.6cm(L x W x T)