How to Read an ASTM D2000 Callout

What a line callout is for

A drawing can name a rubber in three ways: a line callout such as ASTM D2000, an aerospace or military material document such as an AMS specification, or one maker's compound name. A compound name ties the part to one maker, while a callout states the properties the material has to meet, so any compound that meets them can be quoted. ASTM's public scope for D2000 describes a system that groups vulcanized rubber into types by how well it withstands heat aging and into classes by how much it swells in oil, with values for further requirements completing the description. If a product's own detailed specification disagrees with the classification, the product specification wins.

The parts of a callout, in order

1. The document. ASTM D2000 or SAE J200, sometimes followed by a two-digit year after a hyphen that ties the callout to one edition.
2. M, for SI units. A callout that starts with M states its values in SI units, so the tensile digits read in megapascals. Without the M the callout is in inch-pound units, and the tensile digits are read in hundreds of psi.
3. The grade. A single digit. The standard ties each grade to requirements beyond the basic properties, and the requirements a callout adds are the suffixes at its end.
4. The type letter. The level of resistance to heat aging. Each letter stands for the temperature of an air-oven aging test in the standard's tables, and the material has to keep its properties within set limits after it.
5. The class letter. The level of resistance to swelling in oil. Each letter stands for the most the material may swell after immersion in the standard's reference oil, with the limit for each letter set in the standard's tables; letters further along the alphabet allow less swell.
6. The hardness digit. The durometer in tens, so 7 means 70 Shore A.
7. The tensile digits. Two digits for the minimum tensile strength; with the M, 14 means 14 MPa.
8. The suffixes. One group of letters and digits for each added test. The letters name the property, such as B for compression set, EO for oils, EF for fuels and F for low temperature, and a Z marks a special requirement the drawing must spell out. The digits pick the test method and the test temperature from the standard's own tables.

One callout, read part by part

This example was written for this guide: ASTM D2000 M2BG714 B14 EO14 F17.

Read together, it asks for a 70 Shore A material in the BG envelope, with compression-set, oil and low-temperature tests added. BG is an envelope, not a polymer: nitrile and polyurethane can both meet it, which is why the suffixes and the rest of the drawing matter.

SAE J200 and ASTM D2000

SAE J200, Classification System for Rubber Materials, is SAE International's document, and ASTM D2000, Standard Classification System for Rubber Products in Automotive Applications, is ASTM's. The two are kept in step: when SAE revises J200, the matching change is made to D2000. A callout therefore reads the same way under either number. Quote against the document the drawing names, and keep that document on the paperwork.

What a callout does not tell you

• The type letter is the temperature of an aging test, not a service rating for the part. The service range comes from the compound's data sheet and your application.
• A type and class pair is an envelope that more than one polymer can meet, so a letter match alone does not make two compounds interchangeable.
• A callout with no suffixes says nothing about compression set, low temperature or fluid resistance, which are often the properties that decide whether a compound suits the part.
• The tests use reference fluids, so a callout is not a chemical-compatibility answer for the media your part will see.

When all you have is a compound name

Send the compound name with the maker's data sheet, the hardness and the color, and say what the part has to withstand: heat, cold, oils, fuels or water, and how long it stays compressed. A maker's data sheet often prints the D2000 callout the compound meets, and that callout is what another source can quote against. If the drawing names an AMS or MIL document instead, the part is quoted against that document.

Callouts on a custom molded part

On a custom molded part, the callout on the drawing governs on either route: the domestic molders Conquest Seal distributes for, or our overseas manufacturing program with Conquest Seal as the manufacturer of record. The certification names the compound supplied against the callout. The RFQ checklist for custom molded parts lists what else a molded quote needs, and the tolerance class guide covers the dimensions. The part types with their own pages are molded gaskets and seals, grommets and plugs and boots.

Sources

1. ASTM D2000-18(2024)e1, Standard Classification System for Rubber Products in Automotive Applications: the public scope in the ASTM store listing (types by resistance to heat aging, classes by resistance to swelling in oil, values for further requirements, precedence of a product specification), read 2026-09-25
2. SAE J200 (J200_202303), Classification System for Rubber Materials: the SAE Mobilus record (title and scope), read 2026-09-06
3. ASTM D2000 / SAE J200 line callout structure, suffix letters and the J200 and D2000 revision practice, from published manufacturer guides, read 2026-09-06