A: This is referring to inner diameter.
A: Includes reducing washer to transition from 1-1/4 to 1-1/2 in. pipe.
A: Yes if you get an adaptor. You may need to get more than 1 to get from 1" to 1.5".
A: This will fit over 1-1/2" tubular and 1-1/4" tubular with a reducing washer. Typically kitchen sinks are 1-1/2" tubular and restroom sinks would be 1-1/4" tubular.
A: This will not work for that application. You may need to replace the drain on the sink with a 1-1/2" down tube one
A: Yes, this part is designed for use under sink. It comes with directions and may need to be cut to length.
A: You should be able to. Kitchen sink piping is 1 and a half inches wide. Bathroom vanity sinks are usually 1 and a quarter inches wide. So yes, this size is what you want for a kitchen sink.
A: Yes it can.
A: Yes, it is meant for a standard kitchen sink installation.
A: Yes, this is meant for kitchen sinks