If you dive with backup lights, then you will have wondered, where the lights could be mounted on the equipment. On the one hand, they should not interfere with the diving, but on the other hand, they want to be close to hand should the primary light fail. One possible solution is to provide the backup light with a bolt snap carabineer and then attach it to the harness.
Note: I would like to show you how to attach a backup light, which has an eyelet on the top of the outer shell, as is shown in the picture above.
Step 1: Thread the nylon line
In the first step you should thread the nylon line through the eyelet of the light and the bolt snap carabineer twice. Then tighten the line.
Step 2: Cross over the nylon line
Then you must cross over the nylon lines so that the nylon line goes under and along the bolt snap carabineer.
Step 3: Tie nylon line
Now fully tighten the nylon line and thus build up tension. Then tie the line.
Step 4: Burn ends
After you have tied the knot, cut the nylon line about 5 mm from each end. Then melt the ends with a lighter and press the molten line with the bottom of the lighter or a flat screwdriver. This prevents the accidental unravelling of the knot.
The end result should look similar to that in the picture above.
Tip: In order to secure your backup light onto the harness of your backplate you need to clip the bolt snap carabineer into a chest D-ring. Attach a 1 cm wide piece of bicycle tubing to the harness that secures the light head. If you need the backup light, you just have to pull the bicycle tube attached to the light head and then turn the lamp on.