Networx®
Networx T1 / E1 / PRI Crossover Adapter
Bottom line: The Networx T1 / E1 / PRI Crossover Adapter ($9.99 on Amazon as of 2026-10-06): Swaps pins 1-4 and 2-5 to turn any straight-through patch cord into T1/PRI crossover; main trade-off: only crosses T1/E1 pairs - not a substitute for an Ethernet crossover adapter.
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*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
Pros & Cons
Pros
- ✓ Swaps pins 1-4 and 2-5 to turn any straight-through patch cord into T1/PRI crossover
- ✓ Enables back-to-back DTE-DTE router pairing over serial WAN cards for CCNA lab builds
- ✓ Works with legacy muxes, J1 interfaces, and ISDN PRI PBX gear needing a null modem signal
- ✓ Networx Lifetime Warranty covers the adapter
- ✓ RJ45 male-to-female form factor drops into an existing cable run with no rewiring
Cons
- ✗ Only crosses T1/E1 pairs - not a substitute for an Ethernet crossover adapter
- ✗ Requires you to supply your own straight-through patch cable
- ✗ Niche telecom use case with little value outside router labs and legacy PBX work
- ✗ No shielding, cable category, or length spec published for the pass-through
Manufacturer description
Convert Patch Cables to T1 / PRI Crossover Wiring. Eliminate the need to stock specialized crossover cables for telecom installations. The Networx T1 / E1 / PRI Crossover Adapter snaps onto any standard straight-through Ethernet patch cord to create a T1 or ISDN PRI Crossover connection (swapping the Transmit and Receive pairs). This tool is critical for Router Labs, allowing you to connect routers back-to-back (DTE-DTE) via serial WAN cards, or for interconnecting legacy Muxes, J1 interfaces, and PBX hardware that require a null modem signal.
SpecPicks Verdict
SpecPicks scored Networx T1 / E1 / PRI Crossover Adapter using a rating × review-volume × price-fit model applied to published specs and reviews across the retro networking cards category. Networx®'s retro networking cards lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.
Common buyer scenarios for retro networking cards of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.
Key Features
- TELECOM CROSSOVER WIRING: Converts any standard straight-through Ethernet patch cord into a T1 / PRI Crossover cable by swapping the Transmit and Receive pairs (Pins 1-4 and 2-5).
- ROUTER LAB ESSENTIAL: Critical for connecting routers or Voice Gateways back-to-back (DTE-DTE) via serial WAN cards in lab environments or training setups.
- LEGACY MUX AND PBX SUPPORT: Perfect for interconnecting telecom hardware that requires a null modem signal, such as legacy multiplexers, J1 interfaces, or ISDN PRI PBX systems.
- COMPACT ADAPTER: Saves space in your toolkit by eliminating the need to carry specialized T1, E1, or PRI crossover cables.
- LIFETIME WARRANTY: Backed by the Networx Lifetime Warranty.
Full Specifications
| Brand | Networx |
|---|---|
| Color | Blue |
| Finish | Matte |
| Unit Count | 1.0 Count |
| Model Number | LB-T1E1X |
| Warranty Type | Lifetime |
| Connector Type | RJ45 |
| COMPACT ADAPTER | Saves space in your toolkit by eliminating the need to carry specialized T1, E1, or PRI crossover cables. |
| Item Dimensions | 3.56 x 3.25 x 0.78 inches |
| Mfr Part Number | LB-T1E1X |
| Number of Items | 1 |
| Number of Ports | 2 |
| LIFETIME WARRANTY | Backed by the Networx Lifetime Warranty. |
| Compatible Devices | PC |
| ROUTER LAB ESSENTIAL | Critical for connecting routers or Voice Gateways back-to-back (DTE-DTE) via serial WAN cards in lab environments or training setups. |
| Item dimensions L x W x H | 3.56 x 3.25 x 0.78 inches |
| LEGACY MUX AND PBX SUPPORT | Perfect for interconnecting telecom hardware that requires a null modem signal, such as legacy multiplexers, J1 interfaces, or ISDN PRI PBX systems. |
| Global Trade Identification Number | 00845425016553 |
| Full listing title | Networx T1 / E1 / PRI Crossover Adapter - RJ45 Male to Female - Converts Ethernet Patch Cable to Telecom Crossover - for Router Labs and Legacy Muxes |
Ready to buy?
Networx T1 / E1 / PRI Crossover Adapter - RJ45 Male to Female - Converts Ethernet Patch Cable to Telecom Crossover - for Router Labs and Legacy Muxes is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
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