This model is a spherical outer ring type of model NAST-ZZ.
It easily corrects a distortion of the shaft center when the roller follower is installed.
Since the circumference of the outer ring is spherically ground, it helps lighten a biased load (symbol R). (Model number of the type attached with seals is NAST-ZZUUR.)

Model No. Main dimensions Basic load rating Detail specifications CAD Dimensional drawing Inner  diameter di Inscribed bore  diameter dr Outer  diameter D B C Dynamic rating C Static rating C0 2D (DXF) 3D mm mm mm mm mm kN kN NAST 6ZZR 6 — 19 14 13.8 4.12 4.55 NAST 8ZZR 8 — 24 14 13.8 5.68 5.89 NAST 10ZZR 10 — 30 16 15.8 9.7 9.67 NAST 12ZZR 12 — 32 16 15.8 10.4 10.9 NAST 15ZZR 15 — 35 16 15.8 12.3 14.3 NAST 17ZZR 17 — 40 20 19.8 17.4 20.9 NAST 20ZZR 20 — 47 20 19.8 19.2 24.5 NAST 25ZZR 25 — 52 20 19.8 20.7 28.4 NAST 30ZZR 30 — 62 25 24.8 30.3 45.4 NAST 35ZZR 35 — 72 25 24.8 32.2 50.6 NAST 40ZZR 40 — 80 26 25.8 35.7 61.6 NAST 45ZZR 45 — 85 26 25.8 37.1 66.4 NAST 50ZZR 50 — 90 26 25.8 38.7 71.8