Vertically adjustable support for semi-trailer or similar

The device has a fixed outer tube (12), a longitudinally adjustable inner tube (13) and a gear mechanism output shaft with a smaller diameter bevel gear seated on it that belongs to a gear stage driving a spindle drive to move the inner tube. Two large diameter gear wheels are fixed to the shaft in addition to the bevel gear. One is only in the force path of the manual drive and the other only causes and transfers the force flow of the motor drive.