A replacement digit is in communication with a fluid sack or bladder 3. The digit may include pistons 14 that are driven by fluid displaced from the sack when it is compressed, resulting in the digit being able to grip objects. The digit may include return springs to bring it back to a resting position. The digit may be a finger, thumb or toe. The digit and sack may be provided as part of a glove 2. The fluid sack may provide movement possibilities for more than one digit.
