Hi!!!
I fully understand the Centrotec accessories available including as Greg wrote
"the bit holder with a locking detent to avoid the pullout issue but the extra diameter sometimes gets in the way. Michael suggested the ball detent hex drive, also known as an Apex, in that holder."
Yes I want a sq. drive or Robertson bits for my Centrotec chuck, but
what I really want is SAE bits to fit the Centrotec chuck. The ball detent hex drive or APex, or Bit holder BH 60 does not hold a hex shaft drill bit securely enough. When you use this approach, when you pull the bit out of the work most of the time the bit is "stuck" in the work.
I am also aware of after-market work arounds & techniques. For example, I can use a non Fes"kewl" holder designed for the after-market hex SAE bit drill in the Fes"kewl" keyless chuck or just the SAE bit in the keyless chuck, but the whole idea is to be able to use these drills in tight places with quick changes between bits. What I end up doing is swapping the entire keyless chuck holding a drill bit with the Centrotec chuck holding the drive bit. Granted to those who have never seen a Fes"kewl" drill this maneuver has a "wow" factor, however I know in-spite of the fact I have about $700 invested in my Fes"kewl" drill "system".... It's not complete!!! I can't get SAE bits to fit the Centrotec system...... That SUCKS!!!

jim