Abstract 
	Theoretically, the finest guest coating particles may decrease AOR (Angle of Repose, [1]), which is the flowability factor. Although the conjecture is true generally, the effect of guest particle size distribution plays main role in the flow process in storage and handling systems. It means, that both nano and micron particles included inside the size distribution range of coating particles influence the coating process and thus the flowability as well. The wide size distribution causes a lubricant effect among coated particles.  
	In the paper, for investigation of effectiveness of used coating devices and guest particle size distribution, AOR values of the reference sample are measured on Hosokawa Powder Tester. The AOR measured values show excellent coating effectiveness by coating the referent sample with MAIC and Hybridizer, which are typical commercial coating devices.