We're planning a massive DC deployment and need about 200 units of these duplex lc smf transceivers. Do you offer B2B bulk discounts?

Yes, absolutely! For volume purchases like bulk deployments over 100 units, we provide special tiered pricing and dedicated B2B account support. Please hit up our live chat or email sales for a custom wholesale quote.

The specs say operating temp is 0 to 70°C. I need to install these in an unconditioned outdoor cabinet for cell tower backhaul. Do you have an industrial version?

Good catch! The LS-SM551G-A2C is commercial grade (0~70°C) suited for indoor server racks. For harsh outdoor environments, we highly recommend our industrial-grade equivalent which supports extreme temperatures from -40°C to 85°C. You can search for our "LS-SM551G-A2I" model on the site.

Can this DOM sfp module support IEEE 802.3ah-2004 for our specific OAM requirements on a metro ethernet ring?

Yes! It fully complies with IEEE 802.3ah-2004 and SFF-8472 protocols. The built-in DOM (Digital Optical Monitoring) feature ensures you can reliably poll real-time diagnostic data like TX/RX power and temperature directly via your network management system.

Just to be 100% sure before I order, does this optic require single-mode or multi-mode fiber, and what connector type is needed?

This transceiver is specifically designed for Single-Mode Fiber (SMF) to achieve the 120km max distance. You will need a standard Duplex LC connector patch cable to link them up properly.

Hey there, looking to drop this into a mix of Cisco Catalyst and Aruba switches. Will this 1.25g sfp 1550nm module face any vendor-lock issues?

This module is completely MSA compliant and uses standard EEPROM coding. It works seamlessly across multi-brand environments including Cisco, Aruba, and Ubiquiti without triggering any unsupported transceiver warnings.

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Calix SFP1G-ZX120-55 Compatible LINK-PP 1.25G SFP 1550nm 120km Duplex LC DOM SMF Optical Transceiver Module

Name: Calix SFP1G-ZX120-55 Compatible LINK-PP 1.25G SFP 1550nm 120km Duplex LC DOM SMF Optical Transceiver Module
Brand: LINK-PP
SKU: 213618
Price: 21.5 USD
Availability: InStock
Rating: 5 (28 reviews)

# 213618

Product: Calix SFP1G-ZX120-55 Compatible LINK-PP 1.25G SFP 1550nm 120km Duplex LC DOM SMF Optical Transceiver Module
SKU: 213618
P/N: LS-SM551G-A2C
Price: $ 25
Stock: 1164 in Stock
Sold: 998
Product URL: https://www.l-p.com/products/493820.htm

For Order Over $1000 Get $15.00 Off , Code: Linkpp15

For Order Over $3000 Get $50.00 Off , Code: Linkpp50

For Order Over $5000 Get $100.00 Off , Code: Linkpp100

New Users: $10 Coupon for Orders , Code: linkpp2610

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Manufacture: LINK-PP

P/N: LS-SM551G-A2C

Compatible:: Cisco; LINK-PP; Adtran; Alcatel-Lucent; Arista; Avaya; Brocade; Calix; Ciena; Dell; Extreme; FS; Generic; H3C; IBM; Intel; Juniper; NVIDIA/Mellanox; Netgear

Compatible P/N:: SFP1G-SX-31 | 2km; SFP1G-SX-31-I | 2km; 100-01662 | 10km; SFP1G-ELX-31 | 20km; 100-01663 | 40km; SFP1G-EX-55 | 40km; SFP1G-ZX-55 | 80km; SFP1G-ZX-55-I | 80km; SFP1G-ZX100-55 | 100km; SFP1G-ZX120-55 | 120km

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Calix SFP1G-ZX120-55 Compatible LINK-PP 1.25G SFP Specifications

The Calix SFP1G-ZX120-55 Compatible LINK-PP module is a high-performance Small Form-factor Pluggable transceiver designed for long-reach Gigabit Ethernet and Fibre Channel applications. Operating at a 1.25Gbps signaling rate, this single-mode module delivers optimal performance over extended optical links. It features a reliable 1550nm DFB transmitter and a highly sensitive PIN receiver, ensuring exceptional signal integrity and low power consumption across commercial operating environments.

Calix Part Number	SFP1G-ZX120-55	Vendor Name	LINK-PP
Form Factor	SFP	Max Data Rate	1.25Gbps
Wavelength	1550nm	Max Cable Distance	120km
Connector	Duplex LC	Media	SMF
Transmitter Type	DFB	Receiver Type	PIN
TX Power	0 to +5dBm	RX Power	-30 to -1dBm
Receiver Sensitivity	-28dBm	DOM Support	Yes
Operating Temperature Range	0 to 70°C	Protocols	SFF-8472 MSA Compliant, IEEE 802.3ah-2004

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Q: We're planning a massive DC deployment and need about 200 units of these duplex lc smf transceivers. Do you offer B2B bulk discounts? By S***r on 2026-04-17

A: Yes, absolutely! For volume purchases like bulk deployments over 100 units, we provide special tiered pricing and dedicated B2B account support. Please hit up our live chat or email sales for a custom wholesale quote. By admin on 2026-04-17
Q: The specs say operating temp is 0 to 70°C. I need to install these in an unconditioned outdoor cabinet for cell tower backhaul. Do you have an industrial version? By M***z on 2026-01-10

A: Good catch! The LS-SM551G-A2C is commercial grade (0~70°C) suited for indoor server racks. For harsh outdoor environments, we highly recommend our industrial-grade equivalent which supports extreme temperatures from -40°C to 85°C. You can search for our "LS-SM551G-A2I" model on the site. By admin on 2026-01-10
Q: Can this DOM sfp module support IEEE 802.3ah-2004 for our specific OAM requirements on a metro ethernet ring? By N***e on 2025-10-24

A: Yes! It fully complies with IEEE 802.3ah-2004 and SFF-8472 protocols. The built-in DOM (Digital Optical Monitoring) feature ensures you can reliably poll real-time diagnostic data like TX/RX power and temperature directly via your network management system. By admin on 2025-10-24
Q: Just to be 100% sure before I order, does this optic require single-mode or multi-mode fiber, and what connector type is needed? By J***n on 2025-10-09

A: This transceiver is specifically designed for Single-Mode Fiber (SMF) to achieve the 120km max distance. You will need a standard Duplex LC connector patch cable to link them up properly. By admin on 2025-10-09
Q: Hey there, looking to drop this into a mix of Cisco Catalyst and Aruba switches. Will this 1.25g sfp 1550nm module face any vendor-lock issues? By C***s on 2025-07-02

A: Hi! This module is completely MSA compliant and uses standard EEPROM coding. It works seamlessly across multi-brand environments including Cisco, Aruba, and Ubiquiti without triggering any unsupported transceiver warnings. By admin on 2025-07-02

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B***s

Viet Nam

Verified Purchase

5 .0

2026-05-09

Installed these 1550nm transceivers for campus fiber networking. Great value for bulk procurement!

186 Helpful vote Comments

D***r

Costa Rica

Verified Purchase

5 .0

2026-02-27

Used this single-mode module for bridging two buildings. Easy 120km max distance capability!

187 Helpful vote Comments

R***n

Greece

Verified Purchase

5 .0

2026-02-24

Tested this cisco compatible 1g sfp in our core network. Zero packet loss observed.

118 Helpful vote Comments

J***r

Belgium

Verified Purchase

5 .0

2026-02-16

Bulk deployment went smooth. Highly recommended!

40 Helpful vote Comments

C***g

Denmark

Verified Purchase

5 .0

2026-01-24

DOM support works perfectly on my Ubiquiti switch.

39 Helpful vote Comments

A***k

Denmark

Verified Purchase

5 .0

2026-01-12

We deployed 50 of these duplex lc smf transceivers in an outdoor cabinet scenario. Despite nearing the 70°C limit during summer, the PIN receiver maintained zero errors on our base station backhaul.

31 Helpful vote Comments

E***z

Czech Republic

Verified Purchase

5 .0

2025-12-12

Tested the IEEE 802.3ah-2004 protocol compatibility for our enterprise ring topology. The 1550nm DFB transmitter is incredibly stable, making this cisco compatible 1g sfp a massive cost saver for large campus fiber deployments.

68 Helpful vote Comments

R***s

Brazil

Verified Purchase

5 .0

2025-10-11

Solid smf optical transceiver for multi-brand switches!

73 Helpful vote Comments

S***s

Dominican Republic

Verified Purchase

5 .0

2025-08-23

Smooth gigabit ethernet link for our home NAS. The duplex lc connector clicks perfectly.

157 Helpful vote Comments

A***s

Norway

Verified Purchase

5 .0

2025-05-17

Exactly what our server room needed today.

80 Helpful vote Comments

T***h

Poland

Verified Purchase

5 .0

2025-04-20

The 0 to 70°C temp range is adequate for our indoor server rack deployments. ❄️

196 Helpful vote Comments

D***s

Netherlands

Verified Purchase

5 .0

2025-03-21

Ran an OTDR and light meter on this 1.25g sfp 1550nm 120km module. TX power sits beautifully at +2dBm, hitting our remote site 80km away with pristine signal integrity. Elite tier hardware!

38 Helpful vote Comments

T***a

Russian Federation

Verified Purchase

5 .0

2025-03-15

Connected flawless with our Juniper gear. Quality smf optical transceiver module for the price.

198 Helpful vote Comments

B***r

France

Verified Purchase

5 .0

2025-03-07

1550nm DFB laser runs cool and stable.

177 Helpful vote Comments

S***n

Brazil

Verified Purchase

5 .0

2025-01-14

SFF-8472 protocol checks out. Solid buy! ✅

126 Helpful vote Comments

D***N

Austria

Verified Purchase

5 .0

2024-06-01

Based on this, my first purchase from Link-pp, I will definitely continue shopping through Link-pp. The products are top of the line, and the price is almost unbeatable by any other providers.

142 Helpful vote Comments

j***n

Indonesia

Verified Purchase

5 .0

2024-04-12

We have been these for more than three years without any problems.

98 Helpful vote Comments

A***e

India

Verified Purchase

5 .0