This is a Philips Xitanium LED driver for a 50W LED system, designed to operate on a 230V AC input and provide a 42V output with a constant current between 1.05A and 1.2A. The "DS" indicates it's an isolated driver with a single current output, suitable for indoor applications like downlights, spot lights, and track lights, as well as public buildings, retail, and offices.  
Detailed breakdown

• Philips Xitanium: 
  This is a brand of reliable and affordable LED drivers from Philips (now Signify).
• 50W: 
  The maximum power output the driver can handle is 50 Watts.
• 1.05-1.2A: 
  The driver provides a single, fixed output current that can be set within this range, ensuring a specific current for the connected LED module.
• 42V: 
  This is the maximum voltage output of the driver, designed to be compatible with a 42V LED system.
• DS: 
  This stands for "Double-Ended" or "DSi" (Double-Ended, Single-current) and indicates a specific type of isolated driver.