4Life Transfer Factor Classic has been recognized for years as the best colostrum-based transfer factor product for daily immune system support. It contains our original UltraFactor XF® ingredient for safe and proven immune system support.*

• Supports the immune system's natural ability to recognize, respond to, and remember potential threats
• Boosts natural killer (NK) cell activity*
• Contains Certified 4Life Transfer Factor with UltraFactor XF®
• Contains certified 4Life Transfer Factor® to Raise Your Immune I.Q.®*

Supports the immune system's natural ability to recognize, respond to, and remember potential threats4Life