Sony has introduced a new line of XQD format version 2 memory cards, the G Series. As with other XQD cards, the G Series promises fast read and write speeds that are able to match the demanding needs of select cameras, such as the Nikon D4 and D4s.

In turn, Nikon has announced that the D4s will fully support Sony's version 2 XQD cards, with improved write speeds and Raw buffer capacities. With previous XQD cards the D4s could capture 133 12-bit NEF files before filling the buffer. With the G series cards the buffer capacity is increased to 200 shots. 

The G Series has a 400MB/s read rate, which is faster than the preceding S Series' 180MB/s and the N Series' 125MB/s. Write speeds, as expected, are slightly slower at 350MB/s. The G Series cards are offered alongside a USB 3.0 adapter, which Sony says can transfer 60GB of data to an SSD in 3 minutes (CF takes 7 minutes in comparison).

The G Series cards use a second generation PCI Express interface, and are available in three capacities: 32GB (model QD-G32A), 64GB (QD-G64A), and 128GB (QD-G128A). The 128GB card is unique among Sony's XQD format offerings, with both the S Series and the N Series tapping out at 64GB.

Sony does not have prices listed on its website, but the cards can be found at various retailers. B&H, for example, has the cards available for $163.50 USD for the 32GB model, $363.95 USD for the 64GB model, and $799.95 USD for the 128GB model.