Hi!
Ok, so I grabbed a bunch of different bits and the Festool BHS 65 CE. (I have more bits if necessary ...
![Wink [wink]](https://www.festoolownersgroup.com/Smileys/default/winksmiley.gif)
)

Left to right:
DeWalt Extreme Impact Torsion (China); Festool (?); GRK fasteners brand (USA?); Athlet T-Star (Germany); Snap-On ACR, (USA); Snap-On (Czech) (prob. Wera); Wera Classic (Czech); PB Swiss (Switzerland); Festool (?); Spax T-Star (prob. Wera) (Czech), Athlet (Germany), Wiha Y-Bit (?), Würth AW (Germany?), PB Swiss (Switzerland).
DeWalt Extreme Impact Torsion (China) - Festool BHS 65 CE does not engage properly.

Festool (?) - Festool BHS 65 CE does not engage properly.

GRK fasteners brand (USA?) - Festool BHS 65 CE engages properly.

Athlet T-Star (Germany) - Festool BHS 65 CE engages properly.

Snap-On ACR, (USA) - Festool BHS 65 CE does not engage properly. (At all, doesn't even fit all the way down ...)

Snap-On (Czech) (prob. Wera) - Festool BHS 65 CE does not engage properly.

Wera Classic (Czech) - Festool BHS 65 CE engages properly.

PB Swiss C6 (Switzerland) - Festool BHS 65 CE does not engage properly, but well enough to hold bit.

Festool (?) - Festool BHS 65 CE engages properly.

Spax T-Star (prob. Wera) (Czech) - Festool BHS 65 CE engages properly.

Athlet (Germany) - Festool BHS 65 CE engages properly.

Wiha Y-Bit (?) - Festool BHS 65 CE engages properly.

Würth AW (Germany?) - Festool BHS 65 CE engages properly, but does not hold bit.

PB Swiss E6 (Switzerland) - Festool BHS 65 CE engages properly.

Grouped.

So I took some measurements and my observation is that it's really all about the dents (position and deepness). In case of the Snap-On ACR bit, it's simply too thick, I will have to re-check with another one. That it will lock the PB Swiss E6 but not the Würth E6 is interesting, too.
That it locks the PB Swiss C6 but doesn't engage all the way, that baffles me the most. I will check with another one.
Using mostly T-Star, the BHS 65 CE doesn't give me any more trouble than other bit holders.
Anyway, I will take it - and some bits - to the next Roadshow event if I can attend and see what Festool's thoughts on this are.

Kind regards,
Oliver