BILSTEIN B1 Rear Dust Cover Kit for BMW 1 Series F20/F21, BMW 2 Series F22/F23, BMW 3 Series F30/F31/F34 & more

Suspension accessories in OE quality

The Bilstein B1 range covers top mounts (support bearings), protective tubes and bump stops, each matched to Bilstein shock absorbers, springs and suspension kits, plus the right compressors for Bilstein air suspension modules. Every part is made to uncompromising OE quality, so the whole suspension works as it should.

The B1 range at a glance

Top mounts, protective tubes, bump stops, decommissioning kits and compressors – each B1 service part is tuned to the suspension system it belongs to. The range covers nearly every vehicle model and keeps Bilstein dampers and springs performing well and lasting.

Matched to every Bilstein damper and suspension

B1 parts are more than accessories: they complete Bilstein shock absorbers, springs, air suspension modules and kits – from the B3 replacement spring up to the EVO R. Each one plays a key part in the performance and service life of the damper, spring or kit it is fitted with.

Product benefits

Small parts, big effect: B1 parts keep the whole suspension working and its quality intact, for lasting performance and the familiar Bilstein drive.

• Matched to Bilstein dampers, springs, air suspension modules and suspension kits
• Made for the exact model variant
• Available for a wide range of makes and models
• Genuine Bilstein service parts in top OE quality
• Protects the function and service life of the whole suspension

What makes B1 stand out

• A wide accessory range for almost every vehicle type, from small cars to SUVs and sports cars, tuned to Bilstein dampers, springs and kits for consistently balanced, safe handling.
• Top mounts, protective tubes, bump stops and compressors in original quality – developed to OE specifications and tested to the same standards as original equipment.
• Precise fit, so they install just like original parts, with no extra work or adjustment.
• They complete the suspension down to the last detail and keep comfort, stability and safety for the long term.
• Tested durability and OE-standard corrosion protection – made in Germany.
• One compatible Bilstein system means less fitting time and less rework – good for service quality and cost.

The right part for every damper and suspension

• For almost every model, from small cars to SUVs and sports cars: B1 top mounts, bump stops and protective tubes keep the whole suspension working smoothly, protected and precise.
• OE replacement: ideal together with Bilstein B3 springs and B4 or B6 dampers for new-car comfort and safety.
• Tuning: matched to Bilstein performance kits such as B8, B12, B16, EVO S/SE, EVO T1 and EVO R, for precise response and long life.
• Top mounts link the damper to the body. B1 top mounts give precise response and wheel guidance and keep noise out; they are robust, accurately made and matched to each Bilstein system.
• Bump stops cushion the end of long suspension travel and protect the damper from overload. B1 bump stops use a high-strength material that absorbs energy reliably and adds to safety and comfort.
• Protective tubes shield the piston rod from dirt, moisture and stone chips, extending damper life and keeping damping consistent over time.
• When a suspension without electronic valves is fitted to a car with electronic damping, the factory damper control has to be switched off with a matching decommissioning kit. B1 plug-and-play decommissioning kits stop error messages appearing after the suspension change.

Frequently asked questions

Do my shock absorbers need protective tubes?

Yes. Only a very few vehicles run dampers without them. They keep the environment away from the piston rod and seals, which would otherwise shorten the damper's life. If a damper comes without protective tubes, the OE-type tubes from the B1 range fit.

Do I need new top mounts when the shock absorbers are replaced?

Yes, always fit new ones with new dampers. Top mounts are safety-relevant wear parts that develop play or harden with age. New Bilstein top mounts restore precise wheel guidance, comfort and noise insulation, as on a new car.

Do I need new bump stops when the shock absorbers are replaced?

Generally yes. They cushion the end of heavy suspension travel and protect the damper and strut from mechanical overload. They become brittle or deformed with age, and worn bump stops reduce comfort, stability and safety.

When do I need a decommissioning kit?

When a mechanical sports suspension or coilover kit is fitted to a car with adaptive damping. The B1 decommissioning kits switch off the electronic damping control and prevent error messages in the car's electrical system.

Product details

• Bilstein part number: 11-305880
• Part type: Dust Cover Kit, shock absorber
• Fitting Position: Rear Axle
• Bilstein series: BILSTEIN - B1 Service Parts
• EAN: 4025258851941

Vehicle Fitment

Detailed applications

📦 Regal Autosport Shipping Policy

Shipping Destinations

We proudly ship our products across the UK, Europe, the USA, Australia, South East Asia, and other locations globally.There are no regions we restrict shipping to.

Carriers and Delivery Times

• United Kingdom: Royal Mail for small items; DPD Local for parcels up to 30kg.
  Delivery estimate: 1–2 business days.
  

• International:
  

• Small packages: Royal Mail (postal service)
  

• Small/medium/large parcels: DHL Express.
  Delivery estimate: 2–15 business days, depending on destination.
  

Please note: We do not ship on weekends or UK Bank Holidays. Orders placed after 2 PM will be processed the following business day.

Order Processing

Orders placed before 2 PM are typically processed and dispatched the same day.
Orders placed after 2 PM will be processed on the next business day.

Shipping Costs

Shipping costs are calculated automatically at checkout based on the volumetric weight of your order.
We do not offer free shipping — instead, we focus on keeping product prices as competitive as possible.

Tracking

All orders are shipped via tracked and signed-for services.
Tracking information will be provided and can be accessed via:

• Your Regal Autosport account page in Shopify
  

• The respective courier’s website
  

Customs, Duties, and Taxes

• UK Customers: Prices include UK VAT.
  

• International Customers:
  

• UK VAT will be deducted at checkout.
  

• Customers are responsible for all customs duties, import taxes, and fees applicable in their country.
  

• Delivery times may be delayed by customs clearance — time is not of the essence for deliveries.
  

Lost or Damaged Items

In the rare case of lost shipments:

• If the courier confirms the parcel as lost, we will re-ship your order as quickly as possible.
  

For damaged shipments:

• Customers must assist us in submitting a claim with the courier.
  

• After confirmation, we will replace the item or offer a discount, depending on the situation.
  

We take great care in packaging, but please inspect your order upon arrival and contact us immediately if the item is damaged or missing.

Backorders

Orders containing backordered items will be dispatched once all items are available.
We do not split ship orders. If you require partial delivery, please place separate orders for in-stock and backordered items.

Local Pickup and Delivery

We do not offer local pickup or local delivery for online orders due to security verification policies.
However, customers are welcome to visit our store and pay via chip and PIN.

📦 Regal Autosport Shipping FAQs

Where do you ship to?

We ship across the UK, Europe, the USA, Australia, South East Asia, and worldwide.
 There are no regions we restrict shipping to.

Which carriers do you use?

• UK orders: Royal Mail (small items), DPD Local (parcels up to 30kg)
  
  

• International orders: Royal Mail (small packages) or DHL Express (larger parcels)
  
  

How long will my order take to arrive?

• UK deliveries: Typically 1–2 business days after dispatch.
  

• International deliveries: Usually 2–15 business days, depending on location.
  

Please note: We do not ship on weekends or UK Bank Holidays.

When will my order be dispatched?

Orders placed before 2 PM are usually dispatched the same business day.
 Orders placed after 2 PM are processed on the next working day.

How much does shipping cost?

Shipping costs are calculated at checkout based on the volumetric weight of your items.
 We do not offer free shipping — instead, we keep our product prices as competitive as possible.

Will I receive tracking information?

Yes!
All shipments are tracked and signed for. You’ll receive tracking information by email and can also track your order via:

• Your Regal Autosport account page
  

• The courier’s own website
  

Do I have to pay customs charges or import taxes?

• UK Customers: Prices include UK VAT.
  

• International Customers:
  

• We deduct UK VAT at checkout.
  

• You are responsible for any local customs duties, import taxes, or fees.
  

Delivery times may be affected by customs clearance, and time is not of the essence for international deliveries.

What happens if my order is lost or damaged?

• If your shipment is lost, we will re-ship your order once the courier confirms the loss.
  

• If your order is damaged, we will work with you to file a courier claim and either replace the item or offer a discount based on the situation.
  

Please inspect your delivery upon arrival and contact us immediately if there are any issues.

What if my item is on backorder?

Orders containing backordered items will be held until all items are available.
We do not split ship orders. If you require partial delivery, please place separate orders for in-stock and backordered items.

Can I collect my order in person?

We do not offer local pickup or local delivery for online orders due to security verification.
However, you are welcome to visit our store and pay via chip and PIN if you wish to purchase in person.