GROOMING
Grooming
Read beyond the product name: attachments, maintenance and everyday use.
Shaver Head Replacement Interval: Check the Part Number, Not the Brand
Philips publishes six months, twelve months and two years at the same time. Reading the official pages shows why the brand is the wrong unit for this question.
Waterproof vs IP Rating: What IPX7 Actually Means for a Shaver or Toothbrush
The Braun Series 9 Pro Plus page states waterproofing outright and prints no IP code. Reading the standard alongside the product page shows why those are two different kinds of information.