# UNIPAK Solder Paste LF Nr. 3 S Sn97Cu3

**URL:** https://aio.lv/en/product--unipak-4555321--4580565
**Data updated:** 2026-06-10 09:30 (EEST)
**Category:** Miscellaneous repair tools
**Manufacturer:** UNIPAK
**Manufacturer code:** 4555321
**EAN:** 4029072001643
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 12.99 €
**Prices and availability valid until:** 2026-07-16 23:59
**Price without VAT (21%):** 10.74 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--unipak-4555321--4580565

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 22.06.2026 | free |
| Pickup points | 29.06.2026 | 1.99 EUR |
| Courier delivery to door | 29.06.2026 | 4.99 EUR |

## Summary description

UNIPAK Solder Paste LF Nr. 3 S is a high-quality Sn97Cu3 lead-free soldering paste designed for professional plumbing and heating installations. This flux-based paste ensures optimal wetting and reliable joints when soldering copper pipes and fittings. It is formulated for efficient performance in capillary soldering applications, providing excellent corrosion resistance and clean, durable connections in various piping systems.

## Long description

UNIPAK Solder Paste LF Nr. 3 S Sn97Cu3 is a professional-grade, lead-free soldering paste specifically engineered for plumbing and heating installations. This high-quality flux-based compound is designed to facilitate the capillary soldering of copper pipes and fittings, ensuring consistent and reliable results. By promoting optimal wetting of the metal surfaces, it helps create strong, durable, and corrosion-resistant joints that meet the rigorous demands of modern piping systems.
Advantages
The primary benefit of using UNIPAK Solder Paste LF Nr. 3 S is its superior formulation which guarantees excellent flow and adhesion during the soldering process. Because it is lead-free, it is a safer and more environmentally conscious choice for potable water systems. The paste effectively removes oxides from the metal surface, allowing the solder to bond perfectly, which minimizes the risk of leaks and ensures the long-term integrity of the installation. Its consistency allows for easy application, reducing waste and improving efficiency on the job site.
Suitable for
Soldering copper pipes and fittings in plumbing systems
Heating and central heating installations
Capillary soldering applications
Professional HVAC piping work
When it may not be suitable
This product is specifically formulated for copper-to-copper soldering and may not be suitable for joining dissimilar metals or materials other than copper. It is not intended for use in electronic soldering or high-precision circuit board assembly where specialized fluxes are required.
Key specifications
Composition: Sn97Cu3 (Tin-Copper alloy)
Type: Lead-free soldering paste
Application: Capillary soldering
Compatibility: Copper pipes and fittings
How to use
Before application, ensure that the surfaces to be joined are clean, dry, and free of grease or oxidation. Apply a thin, even layer of the UNIPAK Solder Paste LF Nr. 3 S to the end of the pipe and the inside of the fitting. Assemble the joint and heat the connection evenly using a suitable heat source. Once the target temperature is reached, apply the solder wire to the joint, allowing the molten metal to be drawn into the capillary gap by the flux. Allow the joint to cool naturally without disturbance to ensure a solid connection.
What to consider before purchase
Verify that the piping material is compatible with Sn97Cu3 alloy
Ensure you have the appropriate heating equipment for copper soldering
Check local regulations regarding lead-free requirements for plumbing
Usage recommendations
Always clean the soldered joint thoroughly after the process to remove any residual flux, as this helps prevent long-term corrosion and ensures a professional finish. Work in a well-ventilated area to avoid inhaling fumes during the heating process.

## Specifications

### Weight & dimensions

| Feature | Value |
|---|---|
| Weight | 0.115 kg |

## FAQ

### How much does the UNIPAK LF Nr. 3 S Sn97Cu3 Solder Paste cost, and is it available for purchase?

The price is 12.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 44 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 22.06.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer, Bank cards on-line, Apple Pay, Google Pay. All transactions are 100% secure and encrypted.

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All UNIPAK products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized UNIPAK service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

### How can I tell if this product suits my needs?

When making a choice, we recommend paying attention to the key features: weight, compatibility with your devices or usage conditions, material quality, functionality, and warranty terms. These characteristics will help you determine how well the model meets your needs.

## Image

https://aio.lv/img/cache/product/4580565/65968707_large.webp