$SONO call prices double in day

Option traders posted large gains on bullish positions opened in Sonos (SONO) only one session earlier.

Just yesterday, Market Rebellion’s Unusual Activity Service detected the purchase of 3,600 March $15 calls for $0.23 to $0.43 with shares at $13.62. Volume was well above the strke’s open interest of 2,254 contracts before the activity appeared, indicating that it was fresh buying. Market Rebellion co-founder Pete Najarian cited the unusual activity yesterday in choosing the audio-systems retailer for his final trade on CNBC’s “Halftime Report.”

Those calls have traded for as much as $0.70 today, more than twice their average purchase price. The stock rose 3.82% in the same time frame, illustrating the kind of leverage that can be achieved with options.

Long calls lock in the price where a stock can be purchased, gaining with a rally and providing leverage to the underlying shares. The contracts can quickly lose value if the stock stalls or pulls back but also carry less risk than owning the shares themselves.

SONO opened today at $14.16 but has pulled back to $13.62 this morning, down 3.74% on the session.