Automatically records field to 90 degree in all meridians. The Carrier mechanism is smooth, silent and invisible. The patient perceives only the test object to move. Spring check, giving an Audible click to each 15 degree of rotation of the arc in either direction Renders close scrutiny of dial plate unnecessary, and ensures accurate registration. The device can be thrown out of action if silent movement is desired 
The marker a needle is housed in a retractable tube, sprung to Sheath the pint when not actually marking. A set of interchangeable and permanent washable test objects is included with the instrument. The objects subtend angles of 4 degree, 2 degree, 1 degree, ½degre, ¼ degree and are in white, green and red blue objects in the last three sizes are also included. Supplies complete with Transformer to work on 220 Volt A/C mains With 100 charts

Automatically records field to 90 degree in all meridians. The Carrier mechanism is smooth, silent and invisible. The patient perceives only the test object to move. Spring check, giving an Audible click to each 15 degree of rotation of the arc in either direction Renders close scrutiny of dial plate unnecessary, and ensures accurate registration. The device can be thrown out of action if silent movement is desired 
The marker a needle is housed in a retractable tube, sprung to Sheath the pint when not actually marking. A set of interchangeable and permanent washable test objects is included with the instrument. The objects subtend angles of 4 degree, 2 degree, 1 degree, ½degre, ¼ degree and are in white, green and red blue objects in the last three sizes are also included. Supplies complete with Transformer to work on 220 Volt A/C mains With 100 charts