Quick Answer
This Braun Series 3 replacement head guide helps you choose between 21B, 32B and 32S. Choose the replacement head by the part number on your old cassette or by your exact shaver model, not by the words “Series 3” alone. If the old head is marked 21B, start with a 21B replacement. If it is marked 32B or 32S, match that number; 32B is black and 32S is silver.
Braun’s current US service pages list the same ten model references for 21B, 32B and 32S: 320r-4, 320s-4, 330s-4, 320s-5, 330s-5, 3000s, 3020s, 3030s, 3000BT and CruZer5. That supports these three parts for those listed models, but it does not prove that every Braun shaver marketed as Series 3 uses every cassette. If your model is not on that list, confirm the part number before ordering.
For a confirmed 32B or 32S fit, you can view the ShaversHead Braun Series 3 replacement head page. It currently offers 32B and 32S compatible replacement options; it is not a 21B product page.
Last updated: July 27, 2026 | Author: William | Estimated reading time: 8 minutes
21B vs 32B vs 32S: Quick Comparison
| Replacement head | What the marking means | Braun product description | Best starting point |
|---|---|---|---|
| 21B | Black Series 3 foil-and-cutter head | Braun describes it as a Series 3 head with two closeness foils, three flexible blades and a thin shaving head. | Your old cassette or manual says 21B, or your exact model is confirmed for 21B. |
| 32B | Black Series 3+ / Series 3 cassette | Braun describes it as two closeness foils plus a MicroComb, with three flexible blades and a thin shaving head. | Your old cassette says 32B, or your exact model appears on Braun’s 32B compatibility listing. |
| 32S | Silver Series 3 cassette | Braun lists it as the silver counterpart in the same Series 3 replacement-parts family. | Your old cassette says 32S, or your exact model appears on Braun’s 32S compatibility listing and you prefer silver. |
The 21B and 32B are not described with exactly the same cutting layout on Braun’s product pages. Do not promise identical shaving performance simply because both parts are associated with Series 3. Fit and cutting design are separate questions.
How to Identify the Head Your Series 3 Uses
1. Read the number on the old cassette
Turn the shaver off and remove the cassette according to the instructions for your model. Look for 21B, 32B or 32S on the plastic frame or packaging. A visible part number is stronger evidence than the cassette color.
Color is only a secondary clue. A black cassette can be 21B or 32B, while a silver cassette is commonly 32S. Do not choose between 21B and 32B from color alone.
2. Find the shaver model or type number
Check the back of the shaver, beneath or near the pop-up trimmer, on the rating label, or in the original manual. Write down the full reference, such as 3000s, 3020s or 330s-5, rather than relying on a broad label such as “Braun 3.”
3. Compare the model with an authoritative part listing
Braun’s US pages for 21B, 32B and 32S currently show the same model references:
320r-4, 320s-4, 330s-4, 320s-5, 330s-5, 3000s, 3020s, 3030s, 3000BT and CruZer5.
If your exact model is in that set, the three Braun part pages provide a verified starting point for comparison. If it is not in that set, do not infer compatibility from a similar-looking 3xx or 3xxx number. Check the old head marking, the manual, or Braun support before buying.
Braun 21B vs 32B: What Actually Changes?
The most important difference is the cutting design described for each part, not the black plastic color.
- 21B: Braun describes two closeness foils.
- 32B: Braun describes two closeness foils plus a MicroComb.
The two parts also sit in different product descriptions on Braun’s UK replacement-parts site: 21B is presented as a Series 3 head, while 32B is presented as a Series 3+ head. Regional naming and model revisions can make a series label less precise than the part number, so use the exact model and cassette marking when possible.
For the ten model references currently shown on Braun’s US 21B and 32B service pages, both parts are listed as compatible. That means a confirmed model in that list can be evaluated for either replacement family. It does not mean every older Series 3 shaver can be switched from 21B to 32B without checking.
Use this rule:
- If you want a like-for-like replacement, match the number printed on the old head.
- If your exact model is listed for both 21B and 32B, compare availability, price and the cutting design you want.
- If your model is not listed, do not substitute 32B for 21B based only on the Series 3 name.
Braun 32B vs 32S: The Short Version
For the model references listed on Braun’s US service pages, 32B and 32S are both listed as replacement parts for the same shavers. The visible distinction is the cassette finish: 32B is black and 32S is silver. Match the old part number when you can; otherwise confirm the exact model first and then choose the finish or option that is available. See the dedicated Braun 32B vs 32S comparison for the detailed comparison.
Series 3 Replacement Head Decision Table
| What you can verify | Recommended action | Why |
|---|---|---|
| Old cassette is marked 21B | Buy a replacement explicitly identified as 21B, unless your exact model is separately confirmed for another part. | This preserves the original part family and cutting design. |
| Old cassette is marked 32B | Choose 32B. | It is the direct part-number match. |
| Old cassette is marked 32S | Choose 32S. | It is the direct part-number match and silver finish. |
| Old number is missing, but model is one of Braun’s ten listed references | Compare 21B, 32B and 32S listings, then choose according to the verified part family and finish. | The model is the strongest available identification clue. |
| Model is not on the listed references | Pause and confirm with the manual, old cassette, Braun support or the seller. | Series names and similar model numbers are not enough evidence. |
| Shaver is Series 5, 6, 7, 8 or 9 | Do not use a Series 3 cassette. | Braun replacement-head families are series-specific. |
Common Buying Mistakes
Choosing by color alone
Black does not tell you whether the cassette is 21B or 32B. Silver often points to 32S, but color still does not replace a model or part-number check.
Treating every 3xx model as interchangeable
Model numbers that begin with 3 can belong to different revisions or regional variants. Use the full model reference and the replacement-head number.
Confusing a cassette with a foil-only part
A Series 3 cassette combines the foil and cutter assembly. A foil-only replacement is a different product type and may not be the part you need. Match the product description to the component you are removing.
Assuming “compatible” means genuine Braun
A compatible replacement is made to fit a Braun shaver, but it is not automatically a genuine Braun original part. ShaversHead’s Series 3 product page offers compatible 32B and 32S options; check the product disclosure, pack option and return terms before ordering.
Buying before checking what the seller actually stocks
The ShaversHead Series 3 product page currently offers 32B and 32S selections. If your old cassette is 21B, use the identification steps above before treating that product page as the answer.
After You Choose the Correct Head
Replacement is normally a short, tool-free process: switch the shaver off, release or pull off the old cassette as the model manual shows, then press the new cassette into place until it is seated securely. Do not force a head that does not align or click into position. A loose, crooked or difficult-to-install cassette is a fit check, not a normal break-in period.
Braun says to replace the foil-and-cutter block about every 18 months to maintain performance. Replace sooner if the foil is dented or damaged, the shaver pulls hair, you need many more passes, or irritation increases after cleaning and correct installation.
FAQ
Is 21B compatible with Braun Series 3?
21B is a Braun Series 3 replacement head. Exact compatibility still depends on the shaver model and regional part listing. Braun’s current US 21B page lists 320r-4, 320s-4, 330s-4, 320s-5, 330s-5, 3000s, 3020s, 3030s, 3000BT and CruZer5.
Can I replace a 21B with a 32B?
For the ten model references that Braun currently lists on both its 21B and 32B US service pages, both parts are listed as compatible. The parts are not described with the same cutting layout, so use 21B for a like-for-like replacement or confirm the 32B choice for your exact model before switching.
What is the difference between Braun 32B and 32S?
Both are Series 3 replacement-part numbers. 32B is black and 32S is silver. For the model references listed on Braun’s US service pages, both pages show the same compatible models. Match the old number or verify the exact model before choosing by finish.
Does the ShaversHead Series 3 head fit every Braun Series 3 shaver?
Do not assume that from the series name alone. The ShaversHead product page currently offers compatible 32B and 32S options. Use the old head marking or verify your exact model against the supported part listing before ordering.
Are ShaversHead 32B and 32S heads genuine Braun parts?
They are compatible replacement options, not genuine Braun original parts, unless a product page explicitly says otherwise. Braun is a trademark of its respective owner and is used to identify compatibility.
How often should I replace a Braun Series 3 head?
Braun recommends changing the foil-and-cutter block about every 18 months. Actual timing also depends on use, cleaning and visible wear. Pulling, irritation, repeated passes or damaged foil are reasons to inspect the head sooner.
What should I do if the new head will not click on?
Stop and check the part number, model reference and cassette orientation. Do not force the head or continue shaving with a loose cassette. If the exact model and part family are unclear, confirm them with the manual, Braun support or the seller before ordering again.
