I had purchased a 16 cartridge supply of shavers for my existing Proglide shaver. The handle will not grab the shaver heads after the first 3. I have not abused the shaver handle in any way. I have no receipt for the shaver handle because Its about 3 years old but only used alternating with 2 other shaving systems. Bottom line for me is that in my opinion, a Gillette Proglide handle should not fail. I have switched off from using a few other types of shavers in recent years. This was an attempt to focus on one brand only. I'd like to believe that Gillette makes a durable product.