Astro Pneumatic Solar Power Auto-Darkening Helmet

• Comes ready to use no batteries to install
• Features a solar cell power supply with high performance lithium battery backup
• 6 years+ of backup battery life is normal
• Changes from clear to dark in 1/20,000 second
• User adjustable delay time returning to clear
• User adjustable dark shade from shade 9 to 13.
• Meets ANSI standard Z87.1
• 3.85" x 1.5" viewing area
• Ratchet head gear