A chuck for releasably securing an article comprising: a receiving portion comprising a receiving bore having a longitudinal axis, characterized in that the receiving portion has a contoured clamping surface having at least one clamping segment; the at least one clamping segment comprising a first ramp between a trough and a crest, a second ramp between the crest and a depression, and a third ramp between the depression and a stop ridge, wherein the trough, crest, depression and stop ridge are respectively, at a trough distance D T, a crest distance D C, a depression distance D D and a stop ridge distance D S, from the longitudinal axis, wherein D S < D C < D D < D T and wherein the trough defines a trough side of the first ramp; a clamping sleeve accommodated in the receiving bore and being rotatable between a releasing position and a securing position; one or more rollers associated with said at least one clamping segment, the one or more rollers being accommodated between the clamping sleeve and the contoured clamping surface, wherein: when the clamping sleeve is in the securing position, a first roller of said one or more rollers is accommodated in the depression, and blocked by the stop ridge and at least one of said one or more rollers applies a radially inwardly directed force against the clamping sleeve to frictionally hold the article; and when the clamping sleeve is in the releasing position, said first roller is located on the trough side of the first ramp. a receiving portion comprising a receiving bore having a longitudinal axis, characterized in that the receiving portion has a contoured clamping surface having at least one clamping segment; the at least one clamping segment comprising a first ramp between a trough and a crest, a second ramp between the crest and a depression, and a third ramp between the depression and a stop ridge, wherein the trough, crest, depression and stop ridge are respectively, at a trough distance D T, a crest distance D C, a depression distance D D and a stop ridge distance D S, from the longitudinal axis, wherein D S < D C < D D < D T and wherein the trough defines a trough side of the first ramp; a clamping sleeve accommodated in the receiving bore and being rotatable between a releasing position and a securing position; one or more rollers associated with said at least one clamping segment, the one or more rollers being accommodated between the clamping sleeve and the contoured clamping surface, wherein: when the clamping sleeve is in the securing position, a first roller of said one or more rollers is accommodated in the depression, and blocked by the stop ridge and at least one of said one or more rollers applies a radially inwardly directed force against the clamping sleeve to frictionally hold the article; and when the clamping sleeve is in the releasing position, said first roller is located on the trough side of the first ramp. when the clamping sleeve is in the securing position, a first roller of said one or more rollers is accommodated in the depression, and blocked by the stop ridge and at least one of said one or more rollers applies a radially inwardly directed force against the clamping sleeve to frictionally hold the article; and when the clamping sleeve is in the releasing position, said first roller is located on the trough side of the first ramp.