The Cisco HyperFlex deduplication chunk size based on the underlying block size of a data object. This means the deduplication chunk size can be 4K, 8K... 64K, depending on whatever the block size is you chose when creating the data object (eg. VMDK).
Product :
Cisco, HyperFlex [HCI]/4.0, x86
Feature :
Dedup/Compr. Granularity, Efficiency, Data Services