The cropped biker
The women's biker keeps everything that makes the jacket what it is, the asymmetric zip, the lapel, the belted waist, the hardware, and shortens the body to the natural waist. The proportion is the point: cut close and short, it sits over high-waisted trousers, skirts and dresses and lengthens whatever it is worn with.
Lambskin, not cowhide
These are cut in lambskin, which is soft from the first wear and drapes rather than stands. The structure comes from the pattern and the hardware, not from a heavy hide, so the jacket is light enough to wear most of the year and easy from the first day. Expect it to mark and soften with wear; that is what lambskin does.
Fit
Close at the shoulders, close through the body, ending at the waist. It is worn over a t-shirt or a fine knit, not a jumper; a biker that is bought large to fit a jumper under it loses its line. The fit note on each product says which way to go between sizes for that pattern.
Colour and hardware
Black with silver-tone hardware is the classic; the bone and oxblood pieces read as a different jacket altogether. The hardware is the same on all of them, chosen to last rather than to be replaced.