Baroque (B) vs. German (G) Recorders
Check the back of your recorder near the thumb hole for a tiny stamped letter: "B" (Baroque/English) or "G" (German).
Counting down from the mouthpiece (top) toward the foot/bell (bottom): on a German flute, hole 5 is smaller than hole 4. On a Baroque flute, hole 5 is larger.