Just for the sake of clarity, the term 'chips' as it pertains to buying kava, typically indicates pieces of the root stump/corm of the plant. This part is known to be weaker than the lateral roots. In the case of this Medicinal Maui brew or chew, it appears to be either be lateral roots or a mixture of the two.
If it is as potent as you say, my guess would be that it's either a high KL% plant, it hasn't been overly dried and processed (which can degrade the KL%) or it's simply a Hawaiian grown Isa tudei plant. I emailed this company last year and they told me they have 6 or 7 varieties growing, the bulk of which are Mo'i and Hiwa...didn't name the others though.