Thanks Reply !
i will buy Bourns potentiometer. but before buy, if i know torque of my potentiometer, i can understand which torque have which rotation resistance.
because, i should use potentiometer for sensing degree for my wings. so, for wing move it self, should use low torque.
my cheap potentiometer torque is little bit strong. so if i know torque of this, i can predict torque with values.