ROCKBROS 31.8/34.9mm Clamp Aluminum Ultralight Quick Release Road Bike MTB Mountain Bicycle Seat Post Seatpost Clamp 40g 4Colors

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A Golden A Blue A Red A Black B Golden B Blue B Red B Black
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ROCKBROS Aluminum Ultralight Quick Release Road Bike MTB Mountain Bicycle Seat Post Seatpost Clamp 31.8mm 34.9mm 40g, 4Color
Dear customers:
Thank you for your order. There will be
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if the order quantity
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if you care about the tracking information and want to receive it soon. it’s the best you can buy more than 1 in my store.

A 31.8mm/ B 34.9mm
Please confirm the size before you payment.
Brand RockBros
Name Bicycle Seatpost Clamp
Item Number 2011-4
Color Blue, Black, Red, Golden
Size A: 31.8*64*45.5mm B:34.9*65*46.5mm
Material Aluminum Alloy Titanium alloy shaft
Features Ultralight, only 40g

Anti-slip design

Stable and durable


Red 3 31.8mm

Black 4 31.8mm

Blue 2 31.8mm

Golden 1 1.8mm

Red 7 34.9mm

Black 8 34.9mm

Blue 6 34.9mm

Golden 5 34.9mm

How to choose the right seatpsot clamp?

You can find the specification on the bottom of your seatpost. eg: 30.9mm * 350mm

seatpost clamp 28.6mm Fit for seatpost of 25.4mm, fit for most of road bike and fixed gear bike

seatpost clamp 31.8mm Fit for seatpost of 27.2mm, 28.6mm

seatpost clamp 34.9mm Fit for seatpost from 30.4mm to 31.8mm

seatpost clamp 38.5mm Fit for seatpost of 33.9mm, for most of folding bike

(Purchase according to the actual situation, it’s just a suggestion)

Product Details:

Condition: New

Size: A 31.8mm/ B 34.9mm

Weight: 40g

Material: Aluminum


We are proud to offer international shipping services that currently operate in over 200 countries and islands world wide. Nothing means more to us than bringing our customers great value and service. We will continue to grow to meet the needs of all our customers, delivering a service beyond all expectation anywhere in the world.

How do you ship packages?

Packages from our warehouse in China will be shipped by ePacket or EMS depending on the weight and size of the product. Packages shipped from our US warehouse are shipped through USPS.

Do you ship worldwide?

Yes. We provide free shipping to over 200 countries around the world. However, there are some locations we are unable to ship to. If you happen to be located in one of those countries we will contact you.

What about customs?

We are not responsible for any custom fees once the items have shipped. By purchasing our products, you consent that one or more packages may be shipped to you and may get custom fees when they arrive to your country.

How long does shipping take?

Shipping time varies by location. These are our estimates:
Location *Estimated Shipping Time
United States 10-20 Business days
Canada, Europe 10-20 Business days
Australia, New Zealand 10-30 Business days
Central & South America 15-30 Business days
Asia 10-20 Business days
Africa 15-45 Business days
*This doesn’t include our 2-5 day processing time.

Do you provide tracking information?

Yes, you will receive an email once your order ships that contains your tracking information. If you haven’t received tracking info within 5 days, please contact us.

My tracking says “no information available at the moment”.

For some shipping companies, it takes 2-5 business days for the tracking information to update on the system. If your order was placed more than 5 business days ago and there is still no information on your tracking number, please contact us.

Will my items be sent in one package?

For logistical reasons, items in the same purchase will sometimes be sent in separate packages, even if you've specified combined shipping.

If you have any other questions, please contact us and we will do our best to help you out.


Order cancellation

All orders can be cancelled until they are shipped. If your order has been paid and you need to make a change or cancel an order, you must contact us within 12 hours. Once the packaging and shipping process has started, it can no longer be cancelled.


Your satisfaction is our #1 priority. Therefore, you can request a refund or reshipment for ordered products if:

  • If you did not receive the product within the guaranteed time( 45 days not including 2-5 day processing) you can request a refund or a reshipment.
  • If you received the wrong item you can request a refund or a reshipment.
  • If you do not want the product you’ve received you may request a refund but you must return the item at your expense and the item must be unused.

We do not issue the refund if:

  • Your order did not arrive due to factors within your control (i.e. providing the wrong shipping address)
  • Your order did not arrive due to exceptional circumstances outside the control of . (i.e. not cleared by customs, delayed by a natural disaster).
  • Other exceptional circumstances outside the control of

*You can submit refund requests within 15 days after the guaranteed period for delivery (45 days) has expired. You can do it by sending a message on Contact Us page

If you are approved for a refund, then your refund will be processed, and a credit will automatically be applied to your credit card or original method of payment, within 14 days.


If for any reason you would like to exchange your product, perhaps for a different size in clothing. You must contact us first and we will guide you through the steps.

Please do not send your purchase back to us unless we authorise you to do so.

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