Product description Material: Plastic Size: 15 * 5.5 * 4cm Color: Black Caliber: 38-43 mm Flat circle of the M circle: 34-38.5 mm (for 32-50 mm telescope) S-circle curve circle: 31-34 mm (applies to astronomy and telescopes with small openings) Two circles superimposed: 26-28mm (suitable for microscope and astronomy) Quantity: 1 piece 1. To set up Easily align the eyepiece with your phone camera. It only takes less than 1 minute to connect the phone to the optical instrument and get clear pictures. It is an absolute time saver and an image catcher. 2. For a wide range of eyepieces The universal phone adapter bracket is suitable for eyepieces with an outer diameter of caliber: 38-43 mm and can be mounted on most binoculars, monoculars, telescopes and spotting scopes, microscopes. 3. Compatible with most phones Universal adapter bracket for mobile phones with a wide range of widths from. Suitable for more than smartphone models Often used in iPhone, Samsung, LG, Sony, etc.4. Unique design The phone holder is designed to be rotatable and movable to avoid pressing the volume button and power button during use. It also made it easier to align your phone with the adapter, and you can focus as quickly as possible. 5. Compact and high quality material Full size 15 * 5.5 * 4cm. It's light and compact, easy to transport and store. This phone adapter is made of soft but durable rubber and EVA. The aim was to hold your phone in place and protect it from scratches.