A bow compass (right side, with the ring at top) — the spring-bow style with a centre thumb wheel for fine adjustments, used to draw precise circles A drop-point or divider compass (left side) — for stepping off measurements or scribing circles An extension beam/bar (the long rod in the middle) — attaches to the compass to draw larger circles Spare leads in the small black container eraser at the bottom
These sets were standard school and drafting kit from roughly the 1950s–80s.