Looking to protect my electronics. These seem to make sense. Curious about anglers with some experience with these???

Do not have any experience with the locks although I looked at them. Very expensive for what they are. I use anti tamper screws, a stainless fender washer I painted black and plastic bolt cover in place of the thumb screws provided by the manufacturer. This won't stop a determined thief with a Sawsall, but neither will the lock. I only have one side with the screws, but you could do both. I was worried more about someone pulling up and stealing my electronics when I was inside at a gas station. You can get the screws here: https://www.fmwfasteners.com/collections/tamper-proof-screws

The size you need will depend on what units you are running. The size gauges at Lowes or Home Depot in the fastener section will help you determine that. FMW also sells the bits you will need to remove the screws. I went with the hex screws, and also have have two units using the spanner. The spanner head is easier to strip out. The bits and screws aren't the same size.

Interesting, not opposed to saving almost $200 as I would need four!

Could you send me some pics. I’ve got a decent idea how it works but pics would help. Thanks,

Here is a guy that sells kits for Humminbird Helix on Ebay. Pics are there. https://www.ebay.com/itm/255605156624?var=555545284723

Other units need different size screws, but it is all the same idea. The plastic screw covers (large and small) you can get at Lowes in their specialty fastener drawers.

Use Dura Lock!

Ordered and installed! Thanks