This SV228 Bahtinov Mask is made of optical grade acrylic plastic, so it won't damage your telescope. The cover is designed with aluminium frame, which makes it sturdy and long-lasting. It is worth mentioning that it has a red outer cover, as the vibrant red color expresses your passion for astronomy. With thin and lightweight design, you will not upset the balance of the telescope. It is of fast focusing; get the best focus for your telescope quickly and easily.

The SV228 Bahtinov Mask 156mm is made of optical grade acrylic plastic, which is light and soft to protect your telescope. Aluminum  frame; strong and durable  for long service life. Red cover; the vibrant red can express your passion for astronomy. Thin and light design; aluminum material thickness is 2 mm; Focus quickly; Bahtinov masks make the best focus for your telescope quickly and easily.

Aluminum Bahtinov Focusing Mask perfect focusing for your CCD,DSLR or Webcam in seconds. Light weight so you wont upset the balance on your scope.