This table controls the volume of fuel injected into the engine when the ECU detects the engine has initially begun cranking and achieves synchronisation. It should deliver an amount of fuel as required to fire and start the engine whereby the ECU will then transition to the main fuel tables once above the Max Cranking RPM. 

This table will have different units depending on your Tuning Method. 

Volumetric Efficiency/Mass Air Flow tuning method - The percentage of the mass of fuel at 100% VE for an engine at rest needed for priming the engine.

Injection Time/Fuel Flow Rate tuning method - The actual injection time/fuel amount delivered as the prime pulse.