Cheapest prices ever.
Cheaper than previous best deal which was $134 but that deal only lasted minutes.
Local prices for K245 are $265-$359.
General Specifications
Driver size: 50mm
Sensitivity (dB SPL/V @ 1 kHz): 109dB
Rated impedance: 32 Ω
Audio frequency bandwidth: 15 - 25000Hz
Cable(s) length: 5m
Headphone Type: Semi-open
Wearing Style: Over-ear
Foldable: Yes
Detachable Cable: Yes
Dimensions
Weight: 10.4oz / 295g
Notes: This is an international product. But being Amazon hopefully they will honour at least a full-refund in the case of product failure.
There should be more AKG deals as US Prime Day goes live at 6PM. The AKG K361 is currently $136 via Amazon UK as well, so I'd expect cheaper deals for all of these to appear via the Amazon US store, as well as the AKG K371.
I'd be looking at the AKG K361 and K371 over the K275, and probably avoiding the K175 entirely. Even the K245 aren't much to write home about, but there's not a lot of open and semi-open competition at this price point beyond chi-fi gear and Grados.
Some of the deals your posting are hold overs from UK Prime Day sales, and include the K712 as well. The AKG K371, the AKG K702 and the AKG 712 will be the picks of the bunch if they go on sale.