JOVS 4D Laser Phototherapy Mask, Red Light Therapy, 4 Different Wavelengths with FPT Concentration Technology, 3 Modes Portable Mask for Anti-Aging. About this product: JOVS First Technology: In order to improve light utilization, JOVS invented a patented chip to achieve FPT (Focused Photothermal Therapy) focusing of ultra-narrow light. Advantage 1: Reduce the divergence angle to achieve precise 20° irradiation, improve light wave concentration and energy focusing. Advantage 2: Increase the effi