As I said before, Philips & certain other models have built-in adjustable combs. The settings can be changed in 0.5mm increments by a click type slider. The cheaper ones change in 1mm increments.
Do NOT get the one blade. I loved it the first few times I used it, but the blades wear quickly and start to pull hair. Itβs so frustrating. I replaced my Panasonic rechargeable one that was 5 years old with the one blade and I regret my decision every time I use it. I looked it up on amazon and the price for my old trimmer has dropped by roughly 50% since I originally bought it, and I just bought a new one, so thanks for that. ππ»