The bulls loved T-Mobile US earlier in the month, and they're looking for the gains to keep on coming.
Traders snapped up the August 24 calls for $1.05 on June 14. Yesterday they sold those contracts for $1.52 and rolled up to the August 26s for $0.86, with about 11,000 contracts traded at each strike, according to OptionMonster's tracking systems.
Long calls lock in the price where the stock can be purchased no matter how far it might rise. They give investors cheap exposure to gains in the shares and can generate some nice leverage in a rally.