or preferably teeth 315 can be configured such that closing the first binding portion 101 pushes the protrusion 106 such that protrusion 106 applies a resisting tension against the engagement ledge 320 of feature 107 the engagement ledge 320 of feature 107 can sit between or beyond any of the teeth 315 which can provide an adjustable dimension to the binding unit 100 e g can securely bind different thicknesses of materials angle 322 shown in fig7 between the peak of two adjacent teeth radially measured from the hinge 102 can include a suitable number of sizes such as 1 degree 10 degrees or any suitable magnitude of angle 322 therebetween teeth sizes and slopes can be configured to support any number of suitable locked positions for any number of suitable angle degrees 322 locking shelf 319 defines a recess with a depth extending radially away from the hinge 102 to receive and retain the locking ledge 320 of the binding portion 101 the locking shelf 319 can be any number of suitable depths from about 1 millimeter to about 10 millimeters or any suitable sizes therebetween and should be sufficient to provide the locking engagement with ledge 320 the sloped angles of each tooth 315 including ratcheting surfaces 318 and locking shelves 319 can be configured at an angle that generally corresponds with the hinged movement e g the radial arch of binding portion 101 as hinge 102 is pivoted fig6 illustrates another view of binding unit 100 in this view the locking ledge 320 of feature 107 is visible from a top angle and can include a sloped or recessed wall configured in alignment with the teeth 315 of binding protrusion 106 fig7 illustrates a side perspective with binding unit.