Programmable electronic lock for a shutter or a door or similar object, comprising: - at least one electronic key engageable in said programmable electronic lock and configured to allow the opening and/or closing of said shutter or door or similar object by means of a security code; - a containment body installable on said shutter or door or similar object; - a block operatively housed within said containment body and configured to be reversibly switchable in a clamping condition, in which it prevents an opening of said shutter or door or similar object, and a disengaging condition, in which it allows said opening of said shutter or door or similar object; wherein said block comprises reading and decoding means configured to acquire said security code from said electronic key , and wherein said reading and decoding means are configured to generate an enabling signal to block and/or release said block as a function of a congruency check between a pre-stored security code and said security code of said key ; wherein said block comprises reversible locking/unlocking means such as to be actuated electrically and configured to determine said clamping condition or said disengaging condition, said reversible locking/unlocking means comprising a shaped element rotatable about or translatable along a respective axis (X) so as to determine, in a first position, a mechanical interference between said block and said containment body , so as to prevent a relative movement therebetween, and, in a second position, a condition of no mechanical interference between said block and said containment body , so as to allow a relative movement between said block and said containment body ; wherein said electronic key comprises at least one electronic storage device configured to store said security code of said key , electrical power supply means and an electromechanical connection member configured to establish a connection of the mechanical and electrical type with said reversible locking/unlocking means , so as to mechanically engage said electronic key with said block and to electrically connect said electrical power supply means with at least said reversible locking/unlocking means , in an operative condition of use of said programmable electronic lock ; characterized in that it comprises an angular selection system for the rotation of the block of the electronic lock , wherein said angular selection system comprises a plurality of washers insertable between said block and said containment element so as to determine the maximum angular excursion for the rotation of the block and/or the predetermined rotation direction for the opening/closing of the electronic lock itself, said angular selection system comprising two shaped washers positionable alongside each other on one side or on opposite sides so as to determine at least four combinations between angular excursion and rotation direction of the electronic lock . - at least one electronic key engageable in said programmable electronic lock and configured to allow the opening and/or closing of said shutter or door or similar object by means of a security code; - a containment body installable on said shutter or door or similar object; - a block operatively housed within said containment body and configured to be reversibly switchable in a clamping condition, in which it prevents an opening of said shutter or door or similar object, and a disengaging condition, in which it allows said opening of said shutter or door or similar object; <EOS>