Yeah I've been noticing the description '4c' more and more, recently. I always thought (though pretty useless and a really narrow way of classifying what is essentially millions of unique heads of curls, kinks, coils, etc) 4a meant visibly clumping curls and coils all the way down to coffee stirrer sized, and 4b was non-clumping kinks, essentially.

I have a mixture off all sorts- pen sized, pen-spring, coffee stirrer, and loads of the non-clumping stuff, so I just describe myself as in the 4's (though if people want a more accurate description, leaning more towards 4b). I just find it all very subjective and confusing, and this "4c" has me even more confused than ever (as apparently is whoever coined the terms 'kinky crimpy' and 'kinky ziggly')
Products in current rotation:

Terressentials Pure Earth Mud Wash; Elucence MBC (now really just for cowashing, leg shaving or emergencies); Curl Junkie: Repair Me, Deep Fix, Curl Rehab; AOHSR (retiring); Oyin Handmade: Honey Hemp, Hair Dew, J&B; Qhemet Biologics: BRBC (retiring- prefer Oyin HD), AOHC, OHHB; Jojoba Oil for scalp; Castor Oil or Shea butter to seal; Henna & Ayurvedic pastes when I can be bothered.

Still searching for the perfect stylers, but loving CJ CIAB over everything so far