Transmission (1, 30, 60, 80) with a transmission base (26, 51), with a drive shaft (3, 33, 63) that can be connected to a motor, with an output shaft that can be connected to a machine or a component to be driven, with a first gear train (27, 57, 67, 97) that is operatively connected with the drive shaft (3, 33, 63), with a second gear train (28, 58, 68, 98) that is also operatively connected with the drive shaft (3, 33, 63) and is thereby synchronised with the first gear train (27, 57, 67, 97), with a first transmission part (5, 35, 65, 85) contained in the gear train (27, 57, 67, 97), with a second transmission part (17, 39, 69, 89) contained in the second gear train (28, 58, 68, 98), which second transmission part (17, 39, 69, 89) is synchronized with the first transmission part (5, 35, 65, 85) if the first gear train (27, 57, 67, 97) is free of damage, with a locking element (19, 20, 42, 47, 48, 72, 90) arranged on the first transmission part (5, 35, 65, 85) or on the second transmission part (17, 39, 69, 89), characterised in that only the first gear train (27, 57, 67, 97) is operatively connected to the output shaft and that in the event of asynchrony of the first gear train (27, 57, 67, 97) relative to the second gear train (28, 58, 68, 98) caused by damage to the first gear train (27, 57, 67, 97) the locking element (19, 20, 42, 47, 48, 72, 90) is supported at the transmission base (26, 51) and at the first transmission part (5, 35, 65, 85) outside the surface of engagement with other gear parts and locks the first transmission part (5, 35, 65, 85) relative to the transmission base (26, 51). with a transmission base (26, 51), with a drive shaft (3, 33, 63) that can be connected to a motor, with an output shaft that can be connected to a machine or a component to be driven, with a first gear train (27, 57, 67, 97) that is operatively connected with the drive shaft (3, 33, 63), with a second gear train (28, 58, 68, 98) that is also operatively connected with the drive shaft (3, 33, 63) and is thereby synchronised with the first gear train (27, 57, 67, 97), with a first transmission part (5, 35, 65, 85) contained in the gear train (27, 57, 67, 97), with a second transmission part (17, 39, 69, 89) contained in the second gear train (28, 58, 68, 98), which second transmission part (17, 39, 69, 89) is synchronized with the first transmission part (5, 35, 65, 85) if the first gear train (27, 57, 67, 97) is free of damage, with a locking element (19, 20, 42, 47, 48, 72, 90) arranged on the first transmission part (5, 35, 65, 85) or on the second transmission part (17, 39, 69, 89), characterised in that only the first gear train (27, 57, 67, 97) is operatively connected to the output shaft and that in the event of asynchrony of the first gear train (27, 57, 67, 97) relative to the second gear train (28, 58, 68, 98) caused by damage to the first gear train (27, 57, 67, 97) the locking element (19, 20, 42, 47, 48, 72, 90) is supported at the transmission base (26, 51) and at the first transmission part (5, 35, 65, 85) outside the surface of engagement with other gear parts and locks the first transmission part (5, 35, 65, 85) relative to the transmission base (26, 51).