How do I know if the strainer can fit my drain?

Sometimes, the product descriptions on the package or website are so confusing. It is saying that most sinks have a 3.5 inch – 4 inch diameter drain opening. But why the description of some strainers is 4.5 inch?

How do I know if the strainer can fit my drain?

How to Install a Kitchen Sink Basket Strainer

Buy Fackelmann Stainless Steel Sink Strainer, 6.3 Cm - Long Lasting Construction Online at Best Price of Rs 85.5 - bigbasket

Bathroom Sink Strainer, Bathtub Lavatory Sink Drain Strainer Hair Catcher for Laundry, Mop Pool, Utility, Slop, RV Sink, Stainless Steel Drain Filter。 Fit Hole Size from 1.25 ，3 Pack (1.1”)

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4-1/2 in. Kitchen Mesh Sink Strainer in Stainless Steel (2-Pack) - Danco

Frequent asked question for plumbing product

MR.Siga Bathroom Sink Strainer, Utility, Slop, Bathtub Lavatory Sink Drain Strainer Hair Catcher, Shower Drain Strainer, 3 Pack

How do I know if the strainer can fit my drain?

Kitchen SinkShroom the Amazing Kitchen Sink Strainer and Food Catcher that Keeps Your Drain Clog

3-1/2 in. Sink Drain Assembly with Plastic Basket Strainer in Chrome - Danco