Abstract: A two-for-one twisting spindle for threading a thread by compressed air is comprised of a hollow axle with two cylindrical chambers. A thread storage disk with a thread guiding channel is connected to a lower end of the hollow axle, and a thread inlet tube is connected to the upper end. A thread brake comprising a braking cartridge, an upper and a lower braking ring, and a support is arranged inside the first cylindrical chamber. The braking cartridge, in a braking position, rests with an upper end at the upper and with a lower end at the lower braking ring. In a released position, the braking cartridge rests at the support. The lower braking ring is connected to a hollow piston slidable inside the first cylindrical chamber. A jet of compressed air generates a suction effect in the hollow axle and forces the thread from the thread inlet tube through the thread guiding channel.