A very useful information was provided by Sitecom R&D guys:

Please find the information regarding our latest Ralink adapters below;

WL-302    -    VID: 0x0DF6,    PID: 0x002D    -    Ralink RT2771
WL-315    -    VID: 0x0DF6,    PID: 0x0039    -    Ralink RT2770
WL-319    -    VID: 0x182D,    PID: 0x0037    -    Ralink RT2860
WL-321    -    VID: 0x0DF6,    PID: 0x003B    -    Ralink RT2770
WL-324    -    VID: 0x0DF6,    PID: 0x003D    -    Ralink RT2870
WL-329    -    VID: 0x0DF6,    PID: 0x0041    -    Ralink RT3572
WL-343    -    VID: 0x0DF6,    PID: 0x003E    -    Ralink RT3070
WL-344    -    VID: 0x0DF6,    PID: 0x0040    -    Ralink RT3071
WL-345    -    VID: 0x0DF6,    PID: 0x0042    -    Ralink RT3072
WL-608    -    VID: 0x0DF6,    PID: 0x003F    -    Ralink RT2070

Note:
PID: 0x003C, 0x004A, and 0x004D:   --these products do not exist; devices were never produced/shipped--

The WL-349v4 USB dongle (0x0df6,0x0050) will be shipped soon (it isn't available yet), and uses a Ralink RT3370 chipset.
Signed-off-by: Xose Vazquez Perez <xose.vazquez@gmail.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>