Miter gears are a single type of bevel gears where the two rotational axes intersect. 
When speaking of narrow definition of bevel gears with capability to increase or lower speed, miter gears do not have that ability because of the pair’s same amount of teeth. Their miter gear purpose is bound to the modification in transmission path. Because they are a type of bevel gears, the basic characteristic of bevel gears can be found such as presence of gear forms of straight cut, spiral trim and types.
Also, since the shafts can be set to any angle, right now 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 straight tooth miter gears gets the same number of teeth, apart from small differences such as set screw holes and key methods, the same two gears can mate with one another. However, in the case of spiral miter gears, even though the number of teeth are the same, the twisting directions are different. Therefore, the same gear cannot be meshed together, in fact it is necessary to pair the proper and still left handed pairs.
Bevel gears are classified in various types according to geometry:
Direct bevel gears have conical pitch surface and teeth are right and tapering towards apex.