12"X12" Above video of LARGER METAL MIRROR. Laser finish stainless steel IT IS 93% REFLECTIVE AND AMAZING!!! TRUE FIRST SURFACE MIRROR This heavy gauge mirror is designed for FRESNEL LENS BOUNCING Bottom cooking with a Fresnel Lens was a tricky business before these mirrors Glass mirrors would break even at wide focal patterns. These mirrors can accept a beam 8" in diameter or Linear 9"x 3" allowing for redirection of concentrated sunlight with minimal heat gain. CAUTION, THIS MIRROR CAN HET OVER 200F BUT WILL NOT DAMAGE, JUST LET IT COOL OFF BEFORE YOU PICK IT UP. Side 2 has a removable protective film that reveals the PERFECT MIRRORED SURFACE OUT OF STOCK BACK TO GREENPOWERSCIENCE