Key chuck
Albrecht

Non-rotating hood -- chuck is opened and closed via a hex key inserted into side of body
Available with thru-coolant option
Extremely accurate -- Key-Lock models are the most accurate drill chucks available
Short length and integral shank provide greater rigidity
Unique worm/gear arrangement provides high gripping force
Excellent for use on CNC machining centers because sudden braking will not cause chucks to open
Chuck can run both clockwise and counter-clockwise
Balanced to 6,500 rpm; high-speed balancing (up to 30,000 rpm) available upon application
Hex key included
Available with standard or diamond coated jaws