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title: "S-35/53LC20D Kit of two SFP modules (1.25G), Singlemode"
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S-35/53LC20D: BIDI Kit of two SFP modules (1.25G), 20 km, Singlemode

The **S-35/53LC20D** is a pair of SFP transceivers designed to work together and exchange data over a single-mode fiber.

- **S-35LC20D:** It is a **1.25G** single-mode optical SFP module with a single LC connector. It uses **T1310nm / R1550nm** wavelengths (transmits at 1310nm and receives at 1550nm), supports connections up to **20 km** and includes the **DDMI** (digital diagnostic monitoring) function.
- **S-53LC20D:** It is a **1.25G** single-mode optical SFP transceiver with an LC connector. It uses **T1550nm / R1310nm** wavelengths (transmits at 1550nm and receives at 1310nm), supports connections up to **20 km** and includes the **DDMI** function.

## Technical Specifications

- Maximum power consumption: 1 W
- Optical Output Power: min. -9 dBm / max. -3 dBm
- Average Receive Sensitivity: -24 dBm
- Maximum Received Power: 0 dBm
- Loss of Signal Deactivation: -24 dBm
- Loss of Signal Activation: -36 dBm

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Source: https://shop.marcomweb.it/en/sfp/s-3553lc20d-kit-of-two-sfp-modules-125g-singlemode

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