Size:3/4"/1/2"*1/4" Grade:N52 Axially magnetized This block magnet is custom made for one of our customers for use on security products. As you noticed, they are of N52 grade, which means they are very powerful in pull force. They can also be applied for magnetic linear motor. Basically there are three types of linear motor: Cylindrical moving-magnet linear motors; U-channel linear motors and Flat linear motors. The linear motor is often described simply as a rotary motor that has been rolled out flat, and the principles of operation are the same. The forcer (rotor) is made up of coils of wires encapsulated in epoxy, and the track is constructed by placing magnets (usually high power magnets) on steel. The forcer of the motor contains the windings, Hall-effect board, thermistor (to monitor temperature) and the electrical connections. By using a linear encoder, position can be quickly and directly measured at the load for increased accuracy of the load position. packed in small box and then standard export cartons with magnetism shielding foil