Refer to the PDF data sheet for device specific package drawings
The air discharge usually applies to a non-conductive surface of the EUT. Instead of a direct contact with the EUT, the charged electrode of the ESD generator is brought close to the EUT, and a spark in the air to the EUT actuates the discharge. Compared to the contact discharge mode, the air discharge is more realistic to the actual ESD occurrence. However, due to the variations of the arc length, it may not be able to produce repeatable waveform.