A tool-bit holder for varying tool-bit shank profiles, the tool-bit holder having a hub having a longitudinal bore having an open end and a terminating face; a collar fixedly attached to the hub adjacent the open end of the longitudinal bore and disposed annularly about the hub; a sleeve axially slidably mounted along the hub and disposed annularly about the hub; the tool-bit holder characterized by: the longitudinal bore having a first section adjacent the open end thereof, the first section having a first non-circular profile and a first length, and, the longitudinal bore having a second section adjacent the terminating face thereof, the second section having a second non-circular profile and second length, the second profile of a smaller area than the first profile, and the hub having a plurality of radial slots cominunicating with the first section of the longitudinal bore; wherein a proximal end of the collar forms a channel over each radial slot; wherein the sleeve is at least partially within the channel and has a plurality of radial bores, each radial bore of the sleeve being in communication with a respective one of the radial slots of the hub; a detent ball disposed within each of the radial bores of the sleeve and its respective radial slot of the hub and its respective channel of the collar; at least one inner ramp face on the proximal end of the collar for engaging each detent ball wherein the inner ramp face extends radially outwardly and away from the open end of the longitudinal bore; and a spring biasing the sleeve towards the open end of the longitudinal bore wherein the detent ball in each of the plurality of radial bores of the sleeve engages the inner ramp face and the sleeve is slidably positionable along the hub between a locking position and a retracting position; wherein contact between a tool-bit shank (66, 70) having the second profile and the detent ball urges the detent ball radially outwardly against the at least one inner ramp face to a first extent and wherein contact between a tool-bit shank having the first profile and the detent ball urges the detent ball radially outwardly against the at least one inner ramp face to a second extent that is greater than the first extent. the longitudinal bore having a first section adjacent the open end thereof, the first section having a first non-circular profile and a first length, and, the longitudinal bore having a second section adjacent the terminating face thereof, the second section having a second non-circular profile and second length, the second profile of a smaller area than the first profile, and the hub having a plurality of radial slots cominunicating with the first section of the longitudinal bore; wherein a proximal end of the collar forms a channel over each radial slot; wherein the sleeve is at least partially within the channel and has a plurality of radial bores, each radial bore of the sleeve being in communication with a respective one of the radial slots of the hub; a detent ball disposed within each of the radial bores of the sleeve and its respective radial slot of the hub and its respective channel of the collar; at least one inner ramp face on the proximal end of the collar for engaging each detent ball wherein the inner ramp face extends radially outwardly and away from the open end of the longitudinal bore; and a spring biasing the sleeve towards the open end of the longitudinal bore wherein the detent ball in each of the plurality of radial bores of the sleeve engages the inner ramp face and the sleeve is slidably positionable along the hub between a locking position and a retracting position; wherein contact between a tool-bit shank (66, 70) having the second profile and the detent ball urges the detent ball radially outwardly against the at least one inner ramp face to a first extent and wherein contact between a tool-bit shank having the first profile and the detent ball urges the detent ball radially outwardly against the at least one inner ramp face to a second extent that is greater than the first extent.