Miter gears are a miter gear single type of bevel gears where in fact the two rotational axes intersect. When speaking of narrow description 
of bevel gears with ability to increase or lower speed, miter gears don’t have that ability because of the pair’s same number of tooth. Their purpose is bound to the transformation in transmission path. Because they are a type of bevel gears, the basic characteristic of bevel gears exist such as presence of gear types of straight cut, spiral trim and types.
Also, because the shafts could be set to any angle, there are miter gears with non-90 degree (non-perpendicular) angle called angular miter gears. Ever-power is capable of producing angular miter gears with shaft angles in the number of 45 to 120 degrees.
Because a pair of right tooth miter gears gets the same amount of teeth, apart from small differences such as collection screw holes and key ways, the same two gears may mate with each other. However, regarding spiral miter gears, even when the amount of teeth will be the same, the twisting directions will vary. Therefore, the same equipment cannot be meshed together, in fact it is necessary to pair the right and still left handed pairs.
Bevel gears are classified in various types according to geometry:
Straight bevel gears have conical pitch surface area and teeth are straight and tapering towards apex.