If the plastic/rubber ring around your lens is worn out or broken, or you just don’t have a tight enough grip – you might be interested in this new Kickstarter project called band.it.
band.it is an add-on to your lens. It is a flexible soft elastomer band that makes the adjustment of the zoom and/or focus ring easier and potentially preventing or replacing costly repair.
So why should you put the band.it on your lens – it is a sort of protection – and extra layer of flexible soft material that at least in some cases might prevent hard blows to your lens (although to be honest if your lens falls to the ground it will probably break anyway and might fall with the front part first – at least with most front heavy lenses).
The second – more important factor – it should provide better grip than the rubber of the lens ring in your lens because of the deeper groves it has. Third if you have a problem with the rings on your lens (many Nikon lenses has these problems and repair can be expansive) you can either use the band.it instead of a repair or use it as a safeguard just in case (if the band.it break – you can always replace it and it is much cheaper and does not require sending your lens to the lab for days or weeks.
The band.it is able to be stretched and fit over all lenses that we have measured by the creators of this project, from all the major camera manufacturers. The company compiled a list of over 1,000 lenses that were measured by hand in order to custom size band.it precisely. After backing the project up you will be asked about which type of lens you would want to use the band on and be sent the appropriate sized band.