Package information: you will receive 4 goniometer physiotherapy in the package, which includes both inches and centimetres. The transparent design allows you to read and quickly without visual impairment and makes your work easier. Double scales: two rulers are in one body with different scales and 7 inches/18 cm long arms, which can be opened up to 14 inches/36 cm, making it perfect for your drawing and design requirements. A functional tool to meet your measurement and drawing needs in your . rotation: angle meter physiotherapy offers a rotation and can be used on different occasions, which is helpful to accurately determine the movement area of joints in physiotherapy, sports , etc. Wide applications: goniometer can be used to measure the movement area of joints such as elbows, knees and the angle of the , etc. They can also be used to create architectural and horizontal measurements. [Important gifts]These clear plastic goniometers are suitable for artists, builders, designers, , architects, teachers, engineers, students and other people who have drawing needs, and bring many amenities for their work, or lifetime. Material: PVC Color as shown Package Contents: 4pcs goniometer Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.