Manual for Hilti Te2 is
here.
Per Page 11, "Pull the chuck release ring towards the front and remove
the chuck completely. When fitting the chuck, pull the
release ring towards the front and hold it in this position.
Push the chuck onto the guide tube as far as it will
go and release the ring. Rotate the chuck until it engages
and the ring snaps back into its original position |3|. The
TE-C interchangeable chuck or quick-release interchangeable
chuck may be tited to the TE 2-M with chuck
interface |2|."
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