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The documented Conair GMT900 stubble trimmer has 15 motorised settings from 0.4 to 5 mm. Its increments are not uniform: the manual lists 0.2 mm steps through 2 mm, then 0.5 mm steps to 5 mm. That makes it a short-stubble system rather than a long-beard trimmer.
What the scale means in use
A wearer choosing between 0.8 and 1 mm has separate listed settings. A wearer seeking 2.2 mm does not: the next documented setting after 2 mm is 2.5 mm. Check your preferred length against the available positions rather than assuming a continuous digital scale.
The manual also states that the display’s length no longer applies when the comb is detached. A number remaining on the screen is not evidence that an exposed blade leaves that much hair. Inspect the moving comb and its secure attachment before valuing a used unit’s length-control function.
Cleaning the blades is not shower use
The GMT900 instructions prohibit bathing or shower use while permitting the removed blades to be rinsed and dried before reattachment. That distinction corrects a common assumption that any rinseable cutting assembly makes the whole device waterproof.
Charging figures refer to this model
The manual specifies an initial 16-hour charge, then a normal 90-minute charge with a stated 45 minutes of cordless use. These are original instructions, not a test of an old battery or a specification for every product called i-Stubble.
Who should compare a different tool?
Someone keeping a beard longer than 5 mm needs another documented guide system; see the length comparison.
Source: Conair GMT900 instructions. This page interprets the manual and does not report measured battery or cutting performance.
