@dirtdorphins has a couple of old, bypass pruners - each of which has lost one of the grips. I guess they just slid off at some point. I'd purchased some plasti-dip to use to replace them, but the spring (to get them to open) is in the handle in question. So that seemed like a bad idea.
Failing that, I used marine grade, heat-shrink tubing. I chose the marine grade for two reasons. First, it is coated with an adhesive on the inside. If you look closely at the picture below, you can see a little of the glue seeping out on the piece that's been installed. Second, it shrinks at a 3:1 ratio (rather than the standard, 2:1 on normal heat-shrink tubing).
It's very easy to use and/or install. Simply slip it into position and apply heat. I use a $10.00 heatgun from Harbor Freight, but even a good blow dryer, on the highest heat, will do the job. Move the heat around and you'll see the plastic shrink and adhere. It's fairly intuitive to tell when you're finished in that the plastic will tighten up and mold to the handle or item. Another clue (for me) is when a little of the adhesive appears on either end of the plastic.
I purchased this particular heat-shrink tubing from Amazon. But it's available in many other places, too. For this project, I used 1/2" diameter tubing and it was a tight fit. 3/4" or 5/8" may have worked, too. It's available in a bunch of different diameters and lengths, so get the right size for the job. I've also used it for many other repairs.
For example, we have a small, spouted plastic watering container whose spout cracked and then finally broke. The first repair I tried, with superglue, didn't hold. So, instead, I tried some of the heat-shrink tubing. It worked perfectly - almost. I left the heat on it too long and heated the spout to near-melting. Because the tubing just wants to shrink, it did just that and reduced the aperture of the spout just a bit as well.
