John Mayer has released a G-SHOCK watch inspired by his childhood Casio keyboard.

The 43-year-old rocker admitted getting to design the Casio G-SHOCK Ref 6900 by John Mayer timepiece, which is based on his favourite instrument (Casiotone SK-5 Sampling Keyboard) growing up, is "the perfect bridge between my double life as a musician and a watch enthusiast".

He said: “When Casio approached me about the possibility of working together on a G-SHOCK, it actually timed out really well.

“I had already been pretty deep into wearing the 'Mudmaster' models, and something felt cosmically right about a G-SHOCK being the first watch collab I’ve ever done.

“Casio keyboards came to mind as much as the watches did. Then I remembered how important the Casiotone SK-5 was in my life, and it got exciting really fast. It's the perfect bridge between my double life as a musician and a watch enthusiast.”

The design of the watch is described as an 80s-spin on the iconic 1995 G-SHOCK.

Meanwhile, the Grammy-winner previously admitted he never takes his wardrobe choices too seriously because he feels fashion should be a journey of mistakes until you find the right look that works.

He wrote: "You shouldn't let fashion hurt your feelings. If it does, that's a good indicator you're taking it way too seriously. Anybody, at any time, should be allowed to wear whatever they like. Whether it works or not will be for their future self to make peace with.

"God knows I have a very well-documented history of attempts. Take a hat, for example. Do you know how many hats you have to wear before you find the one that actually works? Wearing bad hats is the only path to a good hat. I'm still trying to fail. I'd like to lose on an outfit one out of every ten times. Means I'm trying. Or I'm not. Did you see how my point just crumbled before me? That's what happens when you try to apply too much thought to fashion."

The Casio G-Shock Ref 6900 by John Mayer is available now for $180 over at Hodinkee.com