100:1 reduction, 120 N.m continuous — what the ratings mean
The GBX0801001004F is a planetary gearbox with straight teeth, 80 mm housing diameter, and a 100:1 reduction ratio. That ratio means the input speed is cut by a factor of 100 while output torque is multiplied — but the continuous output torque is limited to 120 N.m at 100 rpm and 30 °C, so the load on the output shaft must stay within that envelope for sustained duty.
94% efficiency and 30,000-hour service life
Efficiency is listed at 94 %, which is typical for a single-stage planetary with straight teeth — the power loss goes into heat and gear mesh friction. The service life is rated at 30,000 hours at 100 rpm and 30 °C, with the gearbox lubricated for life, so no field re-greasing is needed. Noise level is 60 dB at 1 m under no-load — about the hum of a quiet office — so it won't be the loudest thing in a small machine shop.
Obsolete — sourcing reality for the GBX0801001004F
If you need a drop-in replacement with the same 80 mm diameter and 100:1 ratio, you will need to check the mounting dimensions and shaft interface against current GBX or other planetary families — no direct cross-reference is published.