# Optical cable tester Unit UT691-01 650 nm 1 mW, handheld fiber checker

**URL:** https://aio.lv/en/product--unit-ut691-01--11274969
**Data updated:** 2026-03-11 12:03 (EET)
**Category:** Cable testers
**Manufacturer:** Unit
**Manufacturer code:** UT691-01
**EAN:** 6935750569108
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 24.99 €
**Prices and availability valid until:** 2026-07-09 23:59
**Price without VAT (21%):** 20.65 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--unit-ut691-01--11274969

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 25.06.2026 | free |
| Pickup points | 30.06.2026 | 1.99 EUR |
| Courier delivery to door | 30.06.2026 | 4.99 EUR |

## Summary description

Handheld optical cable tester Unit UT691-01 emits a 650 nm red light at 1 mW for visual fault finding and continuity checks in single-mode and multimode fiber links. Designed for quick identification of breaks, bends and poor connections, it is suitable for installers and technicians performing on-site troubleshooting, maintenance and basic verification of fiber runs.

## Long description

The Unit UT691-01 handheld optical cable tester emits a visible 650 nm red light at 1 mW for visual fault finding and continuity checks in both single-mode and multimode fiber links. Compact and battery-powered, this fiber checker is intended for quick on-site identification of breaks, severe bends, and discontinuities in fiber runs. It provides a simple visible-light source for installers and technicians who need rapid basic verification of physical fiber integrity without relying on complex test equipment.
Advantages
The Unit UT691-01 combines portability with a focused visible light output that clearly highlights fiber breaks and poor terminations. Its 1 mW power level and 650 nm wavelength make faults easier to detect by eye in most single-mode and multimode fibers. The handheld design and simple on/off operation enable fast deployment in field troubleshooting and maintenance tasks. The tester requires no complex setup and is compatible with standard fiber connectors for quick checks.
Suitable for
Visual fault location and continuity checks on single-mode and multimode fiber cables
On-site troubleshooting and maintenance of fiber links in buildings and data centers
Quick verification of newly installed fiber runs and connector terminations
Field technicians and installers performing basic integrity checks
Key specifications
Visible wavelength: 650 nm (red light)
Output power: 1 mW
Form factor: handheld, pocket-sized
Power source: battery-powered for portable use
Compatibility: works with common single-mode and multimode fiber types and standard connectors
How to use
Insert the appropriate fiber connector or mate the bare fiber to the tester's output interface, then switch the Unit UT691-01 on to emit the 650 nm red light. Observe the far end of the fiber or the accessible fiber jacket to identify bright light leakage, breaks, or strong bends where the light becomes visible. Use the tester to check connector continuity by looking for visible light at the far end or using an adapter for connectorized fibers. Turn the unit off after inspection to conserve battery life.
Usage recommendations
For safe and effective use, avoid looking directly into the light source and do not view emitted light with optical instruments. Use the tester in a dimly lit environment to increase visibility of the red light. When verifying connectorized fibers, ensure connectors are clean before testing to avoid misinterpreting contamination as a fault. Carry spare batteries and protective caps for the output to maintain device readiness during field work.

## FAQ

### How much does the Optical cable tester Unit UT691-01 cost, and is it available for purchase?

The price is 24.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 42 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 25.06.2026 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 Unit 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 Unit 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/11274969/63883834_large.webp