The ER-SB40 runs a linear motor at 9,800 cuts per minute behind a dial that steps through 19 lengths from 0.5mm to 10mm. GQ found it clears thick growth quickly with few pulls and rates it a strong tool for short beards and stubble, but a large one, awkward to steer around a jawline and heavy in a wash bag. It is waterproof and runs 60 minutes off a charge.
- — High-performance linear motor delivers 9,800 cuts per minute for efficient trimming of thick, dense hair
- — 19 precision length settings (0.5MM to 10MM) with quick-adjust dial for customizable styling
- — Ergonomic rubberized grip provides better control during use
- — Large and heavy, awkward around the jawline and noticeable in a travel bag
- — The battery gauge shows only full, mid or low, with no minutes-remaining readout
- — A 10mm ceiling is too short for anyone growing a beard out