Product Type: Microscope Arms Theory: Stereo Microscope Microscope Accessories Item: Microscope Head Holder Focus Arm Diameter of ring-shaped ring holding the microscope head: (40mm) Diameter of opening for stand post (arbor): (22mm) Color: Black Material: Metal Package Contents: 1 x Focusing Holder Only the above package contents are included; other products are not. Note: Light photography and different displays may cause the color of the item in the picture to differ slightly from the real thing. The allowed measurement error is +/- 1-3 cm. Attention: 1. Due to manual measurement, please allow a small error. Make sure you don't mind before bidding. 2. Please understand that the color may vary depending on the monitor. Attention: Hello, please pay attention to your shipping address when purchasing products. If your receiving information (e.g., name, street, house number, doorbell/email without name, etc.) is incorrect, the order will not be delivered correctly.