If you haven’t heard of this stuff, check out their website > https://sugru.com
I think I saw it advertised on Facebook a few years back, and at the time had a number of frayed cables that this stuff was advertised as fixing. It’s a mouldable rubber compound and feels a little like sticky Blue Tak when you get it out of the packet. It’s easy to mould into whatever shape you need, and after drying for around 12 hours just feels like rubber. Pretty sure they only did black and white when I bought some, but they now make it in a variety of colours and you can pick it up in loads of places, including Amazon. I’ve still got 2 of the 8 packs I originally bought, and whilst the expiry date is August 2016, it still works fine.