An adjustable brush comprising: a brush head , the brush head including: a first plurality of teeth extending along a rotation axis ; and a second plurality of teeth extending along the rotation axis , the second plurality of teeth being rotatable independently of the first plurality of teeth about the rotation axis ; and a handle extending from the brush head ; characterized in that the brush head includes a plurality of arms extending from the handle , wherein the arms define a receptacle for receiving at least a portion of a carriage from which the first and second pluralities of teeth extend; wherein the carriage is rotatably coupled to the brush head , wherein a rotation of at least a portion of the carriage causes a corresponding rotation in at least one of the first and/or second plurality of teeth (106, 206, 706; 108, 208, 708); wherein the brush head includes a first knob , wherein the rotation of at least a portion of the carriage corresponds to a rotation of the first knob , wherein the rotation of the first knob causes a corresponding rotation of at least one of the first and/or second plurality of teeth (106, 206, 706; 108, 208, 708); wherein a rotation of the first knob in a first rotation-direction causes the first and/or second plurality of teeth (106, 206, 706; 108, 208, 708) to transition into a retracted position from an extended position, wherein when in the retracted position, at least a portion of the first and/or second plurality of teeth (106, 206, 706; 108, 208, 708) are disposed within the receptacle defined by the arms . a brush head , the brush head including: a first plurality of teeth extending along a rotation axis ; and a second plurality of teeth extending along the rotation axis , the second plurality of teeth being rotatable independently of the first plurality of teeth about the rotation axis ; and a first plurality of teeth extending along a rotation axis ; and a second plurality of teeth extending along the rotation axis , the second plurality of teeth being rotatable independently of the first plurality of teeth about the rotation axis ; and a handle extending from the brush head ; characterized in that the brush head includes a plurality of arms extending from the handle , wherein the arms define a receptacle for receiving at least a portion of a carriage from which the first and second pluralities of teeth extend; wherein the carriage is rotatably coupled to the brush head , wherein a rotation of at least a portion of the carriage causes a corresponding rotation in at least one of the first and/or second plurality of teeth (106, 206, 706; 108, 208, 708); wherein the brush head includes a first knob , wherein the rotation of at least a portion of the carriage corresponds to a rotation of the first knob , wherein the rotation of the first knob causes a corresponding rotation of at least one of the first and/or second plurality of teeth (106, 206, 706; 108, 208, 708); wherein a rotation of the first knob in a first rotation-direction causes the first and/or second plurality of teeth (106, 206, 706; 108, 208, 708) to transition into a retracted position from an extended position, wherein when in the retracted position, at least a portion of the first and/or second plurality of teeth (106, 206, 706; 108, 208, 708) are disposed within the receptacle defined by the arms . <EOS>