Product review (5 stars): Does the job / government approved
These are not required where I live, but an Insurance Inspector, who was trained in California, wrote me up for not having one on my water heater. It arrived quickly and it was easy to put on. Now my house is multi-State approved.  I think, if we have an earthquake strong enough to knock down a water heater that is bolted to the floor, having no hot water will be the lease of my problems, but what do I know.