New easy-release 38 mm Duraflex hip-belt buckle fitted on all 3G rucksacks (except AK70) made between 2015-2017. The male piece is metal, the female part is nylon. The buckle works by the male part threading through the aperture of the plastic piece, and then sitting flat on top.
This buckle can also be retro-fitted on any model 2G AK rucksack with a 38 mm webbing hipbelt (basically every model) except the AK70. Although it will fit on the AK70, its dual-adjustment strap system doesn't work very well. There is a buckle specifically for the AK70 that is available separately.