In Razz, straights and flushes do not count against you for low, and the ace always plays low. The best possible Razz hand is 5-4-3-2-A, or 5 high, also known as "the wheel" or "the bicycle".
In Razz, straights and flushes do not incur penalties for being low, and the ace consistently ranks lowest. The most superior possible Razz hand is 5-4-3-2-A, which is equivalent to 5 high, also known as "the wheel" or "the bicycle".