Classical V-belts Z, A, B, C, D, E (ISO 4184 / DIN 2215): top width, height, datum width and inside / datum length — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/v-belts-classical-z-a-b-c-d-e/ (sheet CC BY 4.0) Basis: Optibelt and ZZR (DIN 2215 / ISO 4184 widths, heights, datum widths), Gates and Tameson (rounded or differing sections), Dayco and ContiTech Li / Ld rows; disagreements shown, numbers only Catalog version: 2026-10-20 Sizes: see table below - Classical (conventional) V-belts are the older wide section: Z, A, B, C, D, E in ISO 4184 / DIN 2215 and RMA IP-20 (the US also uses AX, BX, CX cogged and AA, BB, CC double-V). The letter stands for the section; in the metric designation the number after it is the nominal top width in mm (A/13, B/17, C/22). Top widths and heights are the numbers in the table; the datum width bd is the groove width at the belt's pitch line (the same numbers the ISO 4183 pulley-groove page uses: Z 8.5, A 11, B 14, C 19, D 27, E 32 mm). - Sources: the Optibelt range sheet and ZZR Parts agree on the DIN 2215 widths and heights (Z 10 × 6, A 13 × 8, B 17 × 11, C 22 × 14, D 32 × 20, E 40 × 25). Gates' catalogue prints D 32 × 19 and E 38 × 25 (E top width 38 instead of 40); Tameson prints D 19 and E 40 × 25. Where they differ both are shown; the belt's maker catalogue is the authority for its own belt. Inch sections are as printed by VBeltSupply (A 1/2 × 5/16, B 21/32 × 7/16, C 7/8 × 17/32, D 1-1/4 × 3/4) and Tameson (B 13/32). - Length conventions. Classical belts are sold by inside length Li (RMA: 'A68' = 68 in inside length, 'B75' = 75 in) or in the ISO / European system by datum length Ld (the length at the pitch line; 'pitch length' is the older name for the same thing). Ld = Li + an add-on that depends on the section. The add-ons below are what two brands print: Dayco (one example per section, Li to Ld, in mm): Z +25, A +33, B +40, C +59, D +76, E +81; ContiTech (every row read, constant per section): A +30 mm, B +45 mm. The two systems differ (A +33 vs +30, B +40 vs +45) and C to E add-ons come from one brand only, so use your belt maker's table, not a single add-on. Outside length La (measured with a tape over the top) is approximate; Aims Industrial gives Z 1, A 2, B 3, C 4, D 5, E 6 in as the outside-to-inside deduction. - Not on this page: sizes between the sections (Y, 5, 8, 20, 25), the 40° belt-angle tolerance, per-length tables, tolerances and matching. McMaster-Carr's V-belt category is linked below for per-belt CAD. - Li to Ld examples as printed: Z16DR (Dayco): Li 406 → Ld 431 mm (+25); A16DR (Dayco): Li 406 → Ld 439 mm (+33); B22DR (Dayco): Li 559 → Ld 599 mm (+40); C43DR (Dayco): Li 1092 → Ld 1151 mm (+59); D79DR (Dayco): Li 2007 → Ld 2083 mm (+76); E144DR (Dayco): Li 3658 → Ld 3739 mm (+81); A60 (ContiTech): Li 1525 → Ld 1555 mm (+30); A82 (ContiTech): Li 2083 → Ld 2113 mm (+30); A98 (ContiTech): Li 2500 → Ld 2530 mm (+30); B35 (ContiTech): Li 889 → Ld 934 mm (+45); B43 (ContiTech): Li 1090 → Ld 1135 mm (+45); B67 (ContiTech): Li 1700 → Ld 1745 mm (+45). section (RMA letter / ISO width) top width b0, mm (DIN 2215 / ISO 4184 tables) datum width bd, mm (ZZR) height h, mm (ISO tables) Gates width × height, mm inch top width × height as printed differences between sources Z / 10 10 8.5 6 10 × 6 3/8 × 1/4 (Tameson) Dayco Z16DR, Tameson 10 × 6 A / 13 13 11 8 13 × 8 1/2 × 5/16 (VBeltSupply, Tameson) Dayco 'A: Profile (13mm X 8mm)' B / 17 17 14 11 17 × 11 21/32 × 7/16 (VBeltSupply); 21/32 × 13/32 (Tameson) the two inch heights differ: 7/16 in is 11.1 mm, 13/32 in is 10.3 mm C / 22 22 19 14 22 × 14 7/8 × 17/32 (VBeltSupply, Tameson) — D / 32 32 27 20 (Optibelt, ZZR); 19 (Gates, Tameson) 32 × 19 1-1/4 × 3/4 (VBeltSupply, Tameson) height 19 vs 20 mm: sources differ E / 40 40 (Optibelt, ZZR, Tameson); 38 (Gates) 32 25 38 × 25 1-1/2 × 29/32 (VBeltSupply, Tameson) top width 40 vs 38 mm: sources differ Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - Optibelt: Belt range: classical V-belt table (DIN 2215 / ISO 4184 width b, height h, Li / Ld) and wedge / narrow belt tables — web — Publisher's page; dimensions are facts — https://santent.in/wp-content/uploads/2020/08/Optibelt-Belt-Range.pdf - ZZR Parts: Classic V-series (DIN 2215 / ISO 4184): top width bo, datum width bd, height h — web — Publisher's page; dimensions are facts — https://www.zzr-parts.com/?p=944 - Gates (Statewide Bearings copy): Industrial V-belt catalogue: section widths and heights, datum and outside lengths — web — Publisher's page; dimensions are facts — https://www.statewidebearings.com.au/wp-content/uploads/2018/06/Gates-Industrial-V-Belts-1.pdf - VBeltSupply: Belt spec guide: inch top width x height for classical, 3V / 5V / 8V, SPZ to SPC; length designation examples — web — Publisher's page; dimensions are facts — https://www.vbeltsupply.com/media/wysiwyg/guides/belt-spec-guide.pdf - Tameson: V-belt size chart: top width and height of Z, A, B, C, D, E, 3V, 5V, 8V, SPZ, SPA, SPB, SPC — web — Publisher's page; dimensions are facts — https://tameson.com/v-belt-size-chart.html - Dayco: Industrial product guide: V-belt Li and Ld examples per section, A 13 x 8, 3V 9.5 x 8, SPA 13 x 10 — web — Publisher's page; dimensions are facts — https://na.daycoaftermarket.com/wp-content/uploads/IND-DR-VB-PG-0619-Industrial-Product-Guide.pdf - acorn-ind.co.uk (ContiTech listing): Wrapped classical V-belt rows with Li and Ld in mm (A, B) — web — Publisher's page; dimensions are facts — https://www.acorn-ind.co.uk/contitech/power-transmission/industrial-belts/v-belts/wrapped-classical-v-belts/?start=240 - acorn-ind.co.uk (ContiTech listing): Wrapped classical V-belt rows with Li (in) and Ld (mm) — web — Publisher's page; dimensions are facts — https://www.acorn-ind.co.uk/power-transmission/industrial-belts/v-belts/wrapped-classical-v-belts/?start=600 - Aims Industrial: How to measure a V-belt: Li, La, Ld definitions; narrow-section inside-to-pitch length additions — web — Publisher's page; dimensions are facts — https://aimsindustrial.com.au/blogs/product-guides/blog-how-to-measure-a-v-belt - ISO: ISO 4184:2025 Belt drives, classical and narrow V-belts, lengths in datum system (standard; sold, not reproduced) — standard — ISO; dimensions are facts [verify license at link] — https://www.iso.org/standard/88704.html - McMaster-Carr: V-belts (classical, narrow, banded) (free STEP/IGES per part, for your own design use; no redistribution) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution [verify license at link] — https://www.mcmaster.com/c81-v-belts No true-size file yet: the published figures do not fix the whole shape; a measured scan is planned. API: https://xemstudio.com/api/geometry?object=v-belts-classical-z-a-b-c-d-e