Markets have gone through two full cycles within four months, says BTIG's Julian Emanuel

The S&P 500 has erased its losses for the year, and the Nasdaq closed on Monday at a record. Some of the names pushing the Nasdaq higher since the March lows include Tesla, eBay, PayPal, Facebook, Microsoft, Amazon and Alphabet. Julian Emanuel, chief equity and derivatives strategist at BTIG, and Mike Santoli, CNBC's senior markets commentator, join "Squawk Box" to discuss what they're watching in the markets as stocks rally.