Amazon has sent out invitations for a mystery press conference on September 6 at the Barker Hangar in Santa Monica, California. The company remained tight-lipped on the exact nature of the event, but if last year's is anything to go by, it's likely we will see several Kindle product refreshes ahead of the busy Christmas shopping period.

"I'd assume it's some more Kindle Fire models, including at least one with a 10-inch screen," said Kerry Rice, an analyst at Needham & Co. "They'll be priced very competitively, at lower price points than most, if not all their competitors."

News of the upcoming event follow a report last month suggesting we could see as many as four Kindle Fire 2 variants revealed. They range from a 7-inch base model with a 1024 x 768 pixel display right through to an 8.9-inch version with a 1920x1200 pixel display. Other variants include 4G connectivity, cameras and all of them are rumored to include a pixel density of 216 PPI.

The Kindle e-readers are likely to receive a refresh as well, with the next-generation devices expected to feature integrated reading lights, following in the footsteps of competitor Barnes and Noble's Nook Simple Touch released back in April.

Amazon's Kindle devices have proven very popular in the UK since their launch two years ago. Earlier this month the online retailer announced that Kindle ebook sales now outpace sales of printed physical books on their website. In contrast, the Seattle-based firm noted last year that it took them almost four years to achieve the same milestone in the US.