This pattern is written with three suggestions for yarn
That is why there are three sets of numbers - one for each type of yarn
You are welcome to choose different yarn with the pattern as well

Gauge:
4 inches should equal:
red heart: 6 rows (+ chain) 8 sets of V (+ 1 dc on end) Loops & Threads: 6 rows (+ chain) 5 sets of V (+ 1 dc on end)
Caron: 5 rows (+ chain) 4 sets of V (+ 1 dc on end)