The lift shaft of a translating style screw jack must be attached to something which prevents the lift shaft from rotating. If it is not, the lift shaft (and the load) will turn and not translate. A feature can be added to a machine screw jack to prevent lift shaft rotation. This type of jack is referred to as a "keyed jack" and is available in upright and inverted models. A keyed jack has a keyway machined along the length of the lifting screw. A matching key is fastened to the cover of the jack which will eliminate lift shaft rotation. The keyway in the screw causes greater than normal wear on the internal drive sleeve threads, somewhat reducing jack life.

Ordinary screw jack: The object being lifted is fixed and does not rotate, and the head of the screw rod is fixed with the lifting object, so that the screw rod only lifts and does not rotate. If there is no fixed object to lift the ordinary screw, then the result can only be that the screw rotates without lifting. Because the screw is driven by the worm gear, if the screw is not guided by external force, the screw will only rotate with the worm wheel.

Keyed anti-rotation screw jack: The object to be lifted is not fixed or suspended, and the guide groove is opened on the screw rod to prevent rotation, so that the screw rod can be lifted and lowered along the guide groove without rotation. The anti-rotation type also has shortcomings. When the screw with guide groove passes through the worm wheel, it will wear the worm wheel more easily than the ordinary type. Therefore, if you can choose the ordinary type, it is recommended to choose the ordinary type as much as possible.