The Hellbender bearing is named after a salamander that thrives in the mud, it makes sense that the new all-stainless bearing has an improved seal structure for keeping out water and debris.
Instead of having the casing, or the webbing, for the balls to sit inside, it's completely contacting all the way around.
There's an extra six ball bearings tucked up in there (over what you'd find in Cane Creek's typical 41-millimeter cartridge) – think Enduro Max.
The Hellbender's sealing is also more robust than what you'll find in Cane Creek's other headsets.
The reason for that extra sealing? The IS Slamset top assembly has lost its sealing elements because of the emphasis on creating a low stack height; as a result, the Hellbender bearing has to house all of the seal elements required to keep it from getting contaminated and freezing up.
Makes for an ideal lower bearing upgrade for year-round riding in wet environments - retrofittable to Cane Creek's 40 series, 110, Air and Angleset headsets and perhaps other brands – check size/fit for compatibility.