This is a lithium battery charging module from Parallax Power.  

Engineered for compatibility with lithium batteries, this module ensures efficient and safe charging, optimizing the performance of your RV's energy storage. With its advanced technology and Parallax Power's commitment to reliability, the 4400LBU provides a seamless integration solution, offering peace of mind and extended battery life for your on-the-go adventures.

Features:

• Lithium Battery Optimum Charging Module
• Assembled in North America using US Steel
• 13.9 Float Mode Maintaining Full Charge
• 4 Hour Charging @ 14.0 VDC

Warning: Product may contain materials cautioned by California Proposition 65