Double nut

Claim 1

A double nut comprising: a first nut body having a threaded axial bore, said first nut body being formed with a recess defined by an annular internal surface and arranged in communication with said axial bore; a second nut body having a threaded axial bore coaxial with and corresponding in diameter to said axial bore of said first nut body to provide a common axis, said second nut body being formed with an annular axial projection insertable into said recess and having an annular external surface; at least one of said internal surface and said external surface being conical with a diameter decreasing progressively in a direction of insertion of said axial projection into said recess; one of said recess and said axial projection being eccentric relative to said common axis; and a frangible connecting web breakable at a predetermined circumferential shearing force producing a broken web portion extending in a direction intersecting said common axis to connect said external surface to said internal surface, wherein a portion of the axial projection is axially spaced from the recess and substantially only said broken web portion engages with said conical surface for providing local wedging contact when securely locking the double nut onto a threaded bolt shank.