Milan 2013: Achille Castiglioni's iconic Parentesi lamp has been updated with a flat LED light source by designer Konstantin Grcic, who presented his redesign at Euroluce in Milan last week.

Created for Italian lighting brand Flos, which has produced the Parentesi lamp since 1972, Konstantin Grcic's OK lamp comprises a flat LED disc that slides up and down a steel cable and rotates 360 degrees.

The design is an update of Castiglioni's classic Parentesi lamp, itself a version of a 1969 concept by his friend Pio Manzù, who died before it could be realised.

The cylindrical weight hanging at the bottom of Castiglioni's design has been replaced with a conical weight that's easier to install, but the small spun metal ceiling rose remains exactly the same.

The name of the new lamp combines the round "O" shape of the disc and the first initial of the designer's name. OK is available in white, black, yellow and nickel.

Grcic's Medici chair recently won the furniture category in the Designs of the Year Awards, and he launched an accompanying chair and table this year in Milan.

In January he also unveiled a bench system based on the iconic Barcelona Chair by Mies van der Rohe – see all design by Konstantin Grcic.

Grcic was among several designers, including Marcel Wanders, Yves Behar and Tom Dixon, interviewed by Dezeen in Milan last week – see all our coverage from Milan.

Last year in Milan, Flos presented a lampshade by Paul Cocksedge that allowed visitors to stick their heads inside to view an animation.

Here's some more information from Flos:

"It is a truly enlightening story of design evolution, the one of the Parentesi lamp. Pio Manzù’s original idea of creating a 'light source that can slide vertically from floor to ceiling and rotate 360 degrees on its axis' was adapted by Achille Castiglioni after his friend’s early death in 1969. A beautiful original illustration reveals the painstaking process of refinement that transformed the first schematic concepts into the final product. FLOS launched the Parentesi lamp in 1972 and it has been in continuous production ever since.

"Forty years later, much has changed. The world of lighting has seen a fundamental shift from conventional bulbs to a variety of new lighting technologies which in themselves are creating new opportunities for the design and manufacturing of lamps. Designing a lamp is no longer limited to working around a given bulb. Today, it means designing the actual bulb or light source. This challenged me to think of Parentesi, a lamp that celebrated the traditional bulb in the most effective and beautiful way. Would it be possible to rethink the Parentesi lamp once more and pass the Manzù-Castiglioni torch on to the future?" - Konstantin Grcic.

A light-emitting disk. A sun hanging from a wire. A luminous circle embracing space. All of these are OK, a flat circular shape with a wire that works like a rail and runs from the ceiling to the floor. The name incorporates the shape of the “O” and the first initial of its German designer, Konstantin. Once again, Grcic unites technological experimentation, design sensitivity and a taste for unadulterated shapes. His passion for technology and materials translates into design that speaks the languages of simplicity, innovative avant-garde and design history.

And so Grcic pays homage to an icon of Italian industrial design, redesigning the original light bulb as an ultra-flat LED surface with edge-lighting technology, directable over 360 degrees. The parenthesis-shaped tube of the original lamp maintains its vertical sliding function over the steel cable, but has now become a small rectangular box that houses the electronic components and a soft-touch switch.

The formerly cylindrical weight has been substituted by an easier-to-install cone shape. Only the small ceiling rose, designed by Achille Castiglioni, has remained identical: a beautifully shaped piece of spun metal. OK is available in white, black, yellow and nickel.