Alright, it's teardown time.
Simple design. Leaf spring. Silicone drainback valve, no bypass. The filter material measures out to 75mm tall x 48 pleats and each pleat is 20mm deep (x2) so it's about 144000 square mm of filter material. No plastic or paper in the construction at all. Overall, it looks like a great filter, as you'd expect for Japanese made OEM. Well worth the current $8 or so. EDIT: Just bought four more of these at $5.79 from Hart Nissan of NOVA. For that price this filter is a steal.