# Drill bit Proline 78120K — metal drill bit Ø12 mm, length 151 mm, 1 pc

**URL:** https://aio.lv/en/product--proline-78120k--11720584
**Data updated:** 2026-03-08 11:23 (EET)
**Category:** Drill Bits
**Manufacturer:** Proline
**Manufacturer code:** 78120K
**EAN:** 5903755154170
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 14.99 €
**Prices and availability valid until:** 2026-07-16 23:59
**Price without VAT (21%):** 12.39 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--proline-78120k--11720584

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 08.07.2026 | free |
| Pickup points | 13.07.2026 | 1.99 EUR |
| Courier delivery to door | 13.07.2026 | 4.99 EUR |

## Summary description

Single Proline drill bit model 78120K designed for metalworking. Diameter 12 mm, overall length 151 mm, sold as 1 piece. Suitable for drilling through metal sheets and components where a 12 mm hole is required. Use with compatible drill chucks at appropriate speed and cooling for metal drilling.

## Long description

The Proline 78120K metal drill bit is a single HSS-Co twist drill designed for creating precise 12 mm holes in metal. With an overall length of 151 mm and a 135° point angle with chamfering adjustment, this drill bit is machined entirely by grinding to ensure accuracy and straightness of drilled holes. The bit is produced from high-class high-speed steel with 5% cobalt, offering improved heat resistance and wear performance when drilling hard and alloyed steels, stainless steels, titanium, cast iron and other difficult-to-machine materials.
Advantages
This 12 mm Proline drill bit combines a 135° split point for fast, low walking starts and reduced need for center punching with full grinding manufacture for dimensional accuracy and straightness. The 5% cobalt HSS composition increases thermal stability and tool life during high-temperature cutting, while the geometry and chamfering adjustment help maintain efficient chip evacuation and consistent hole quality. Supplied as a single piece in a blister pack, the bit is suitable for use with standard drill chucks and machine tools when appropriate speeds and coolant are applied.
Suitable for
Drilling through alloyed and high-strength steels
Creating holes in stainless and acid-resistant steels
Working with titanium and creep-resisting steels
Drilling cast iron and other difficult-to-machine metals
Use in hand drills and drill presses with correct speeds and cooling
Key specifications
Drill type: HSS-Co (high-speed steel with 5% cobalt) twist drill
Diameter: 12 mm
Overall length: 151 mm
Point angle: 135° with chamfering adjustment (split point)
Manufacturing method: fully ground flutes for high accuracy and straightness
Material suitability: high-alloy steels, stainless and acid-resistant steels, titanium, creep-resisting steels, cast iron
How to use
Install the 12 mm Proline drill bit securely in a compatible chuck, ensuring correct clamping depth and concentricity. Select an appropriate cutting speed and feed for the workpiece material; use lower speeds and steady feed when drilling hard, heat-resistant alloys. Apply cutting fluid or coolant for heat control and improved chip evacuation when drilling stainless steels, titanium or high-alloy steels. Start drilling with light pressure to establish the hole, then increase to a steady feed while maintaining alignment and avoiding side loads on the bit.
Usage recommendations
For best results, use the drill with a rigid setup (drill press or CNC) when possible, maintain recommended speeds for the specific material, and keep the cutting zone cooled. Re-sharpen slightly rounded points only with appropriate grinding equipment to preserve the 135° geometry and avoid excessive heat during reconditioning.

## Specifications

| Feature | Value |
|---|---|
| Length | 151 mm |
| Metal drill bits diameter | 12 |
| Number of drill bits | 1 pc(s) |

## FAQ

### How much does the Drill bit Proline 78120K Ø12 mm, 151 mm cost, and is it available for purchase?

The price is 14.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 200 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 08.07.2026 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 Proline 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 Proline 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

## Image

https://aio.lv/img/cache/product/11720584/67193509_large.webp