  We describe a Lagrangian defining the preon sector of the knot model. The
preons are the elements of the fundamental representation of SLq(2), and
unexpectedly agree with the preons conjectured by Harari and by Shupe. The
leptons, neutrinos, up and down quarks, described as $j=3/2$ representations,
and the electroweak vectors, described as $j=3$ representations, of SLq(2) also
have the preon composition required by the schemes of Harari and of Shupe. The
coupling constants and masses required by the preon Lagrangian introduce form
factors that are simple functions of the knot model parameters. As previously
shown the knot model has similarly provided a possible parametrization of the
masses and electroweak coupling constants (Kobayashi-Maskawa matrix) of the
standard model. There is an alternative formulation of the kinematics
permitting possible additional isotopic partners of the quarks and the
neutrinos.
