Revelation 9:10

And they had tails like unto scorpions, and there were stings in their tails: and their power was to hurt men five months.

Cross-references

In Revelation 9:3, the locusts receive scorpion-like power; here that power is specifically located in their tails.

Revelation 9:5 states the five-month torment limit; here the locusts' tails are the instrument of that torment.

Revelation 9:19 says horses' tails are like serpents with heads; here locusts' tails have scorpion stingers. Both use tails as weapons in different plagues.