Good product
I needed a simple heel lift to correct a leg length discrepancy.  The rubber heel lift does the job.  It is rubber, so it feels heavy in the shoe; otherwise, it gets 5 stars, but one really should expect this from the rubber lift.  I have no doubt the lift will last just about forever.  I have since tried cork lifts; they also do the trick and are much lighter.
Rating: 4 stars