O-Ring 12x3.5 NBR 70 ShA

O-Ring 12x3.5 NBR 70 ShA – 100 pcs

O-Ring 12x3.5 NBR 70 ShA – 100 pcs is a GRN commercial pack containing 100 elastomeric sealing rings. Each O-ring has a nominal inside diameter d1: 12 mm and cross-section d2: 3.5 mm and is manufactured from NBR – Nitrile Butadiene Rubber with a nominal hardness of 70 Shore A.

The key identification of this commercial variant is:

12x3.5 + NBR + 70 ShA + 100 pcs

The 100 pcs pack quantity is deliberately included in the product identification because it distinguishes this offer from other commercial pack sizes of the same technical O-ring.

O-Ring 12x3.5 NBR 70 ShA – 100 pcs Pack

This product is supplied as a pack of 100 identical O-rings.

The parameters 12x3.5 NBR 70 ShA identify each individual sealing ring, while 100 pcs identifies the commercial pack offered on this product page.

What Is Included in the 100 pcs Pack?

The sales unit contains:

100 pcs of O-Ring 12x3.5 NBR 70 ShA

Each sealing ring in the pack has the same nominal specification:

inside diameter d1: 12 mm

cross-section d2: 3.5 mm

material: NBR

nominal hardness: 70 ShA

The quantity of 100 pcs defines the number of O-rings supplied in this commercial package. It does not change the dimensions or material specification of an individual sealing ring.

Dimensions of Each O-Ring

The designation:

12x3.5

represents:

inside diameter x cross-section

The principal nominal dimensions of each O-ring are:

d1: 12 mm – inside diameter

d2: 3.5 mm – cross-section diameter

The complete nominal size is:

12x3.5 mm

Based on nominal geometry, the outside diameter is:

nominal outside diameter: 19 mm

The 19 mm value is geometrically derived from d1 and d2 and is not a third basic dimension in the O-ring designation.

NBR 70 ShA – Material and Hardness

The O-rings are manufactured from:

NBR – Nitrile Butadiene Rubber

with a nominal hardness of:

70 Shore A

NBR identifies the elastomer family, while 70 ShA identifies its nominal hardness on the Shore A scale.

These characteristics should always be considered together with the 12x3.5 mm dimensions when selecting an O-ring.

The generic NBR designation does not identify the exact compound formulation. Therefore, an exact operating temperature range, maximum pressure or detailed chemical-resistance limits should not be assigned to this product without documentation for the specific GRN compound.

Why Is 100 pcs Part of the Product Identification?

For this product page, 100 pcs is an important commercial characteristic.

The technical identification of each individual sealing ring remains:

12x3.5 NBR 70 ShA

while this particular product page represents:

a pack containing 100 pcs

Making the pack quantity visible directly in the H1 and product description allows buyers to identify the sales unit immediately without having to infer quantity from price or cart information.

It also clearly separates this product page from other pack quantities of the same O-ring.

O-Ring Construction and Sealing Principle

Each O-ring is a closed elastomeric sealing ring with a circular cross-section.

Unlike a radial shaft seal, an O-ring does not incorporate a metal case, garter spring or separately formed sealing lip.

When installed in an appropriately designed groove, its circular elastomeric cross-section is compressed between the mating surfaces. Elastic deformation generates the contact pressure required to establish the seal.

The required compression depends on the sealing arrangement and groove geometry.

Selecting the Correct 12x3.5 NBR O-Ring Pack

Before ordering this product, verify:

• inside diameter d1: 12 mm
• cross-section d2: 3.5 mm
• material: NBR
• nominal hardness: 70 ShA
• required quantity: 100 pcs
• compatibility with the operating medium
• operating temperature
• pressure
• groove geometry
• required compression
• static or dynamic sealing arrangement

Matching only the inside diameter is insufficient. The cross-section, elastomer material and hardness are also part of the technical identification.

Likewise, matching the dimensions alone does not establish complete interchangeability if another O-ring uses a different elastomer or hardness.

Technical Specification – 100 pcs Pack

FAQ – O-Ring 12x3.5 NBR 70 ShA 100 pcs

How many O-rings are included in this pack?

This commercial pack contains 100 pcs of O-Ring 12x3.5 NBR 70 ShA.

What are the dimensions of each O-ring?

Each sealing ring has a nominal inside diameter d1: 12 mm and cross-section d2: 3.5 mm.

What does 12x3.5 mean?

The first value identifies the 12 mm nominal inside diameter, while the second identifies the 3.5 mm nominal cross-section diameter.

What material are the O-rings made from?

The O-rings are manufactured from NBR – Nitrile Butadiene Rubber.

What does 70 ShA mean?

It specifies a nominal elastomer hardness of 70 on the Shore A scale.

Does 100 pcs indicate a different O-ring size?

No. 100 pcs identifies the number of O-rings in this commercial pack. The nominal size of each individual O-ring remains 12x3.5 mm.

What is the nominal outside diameter?

The nominal outside diameter derived from the 12x3.5 geometry is 19 mm.

What should be checked before ordering?

Verify the 12x3.5 mm dimensions, NBR material, 70 ShA hardness, required 100 pcs quantity, operating medium and installation conditions.

AI Overview

O-Ring 12x3.5 NBR 70 ShA – 100 pcs GRN is a commercial pack containing 100 elastomeric sealing rings. Each O-ring has a nominal inside diameter d1: 12 mm and cross-section d2: 3.5 mm and is manufactured from Nitrile Butadiene Rubber (NBR) with a nominal hardness of 70 Shore A.