Y35 / Y750 / PAT750
Current Burndy U-die product pages list these tool families for applicable 12-ton U dies.
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Burndy die-index reference
Burndy Die Chart & Crimp Die Index Reference
Use the die index printed for the connector—not just conductor size or die color. This source-backed reference summarizes selected Burndy copper lug/splice die rows and explains how U/W die families relate to installation tools.
Crimping evidence chain
Tool → head/jaw → die family → conductor → connector → die/index → documented approval or classification. Physical fit alone is not enough.
Last technical review: August 26, 2026.
How to use this Burndy die chart
The table below is a selected field reference for common copper lug/splice rows from Burndy's compression catalog. It intentionally does not reproduce the entire manufacturer chart. Start with the exact Burndy connector; confirm conductor material/size and its printed die index; then use the current Burndy catalog to verify die/tool requirements.
Scope:
Do not use this selected copper lug/splice table for aluminum connectors, C-taps, H-taps, grounding connectors, flex-conductor special cases or overhead sleeves unless the connector documentation explicitly points to the same die/index.
Selected Burndy copper lug/splice die reference
| Conductor | Burndy W die | Burndy U die | Color code | Die index |
|---|---|---|---|---|
| #6 | W5CVT | U5CRT | Blue | 7 |
| #4 | W4CVT | U4CRT | Gray | 8 |
| #2 | W2CVT | U2CRT | Brown | 10 |
| #1 | W1CVT | U1CRT-1 | Green | 11 |
| 1/0 | W25VT | U25RT | Pink | 12 |
| 2/0 | W26VT | U26RT | Black | 13 |
| 3/0 | W27VT | U27RT | Orange | 14 |
| 4/0 | W28VT | U28RT | Purple | 15 |
| 250 kcmil | W29VT | U29RT | Yellow | 16 |
| 300 kcmil | W30VT | U30RT | White | 17 |
| 350 kcmil | W31VT | U31RT | Red | 18 |
| 500 kcmil | W34VT | U34RT | Brown | 20 |
| 600 kcmil | — | U36RT | Green | 22 |
| 750 kcmil | — | U39RT | Black | 24 |
Source: Burndy Compression Connections master catalog, Die Index Chart. Always check the current connector-specific instructions; special/flex and other connector families can use different codes or dies.
What the prefix tells you
Burndy's Die Index Reference explains that die prefixes identify installation-tool families. For example, the U prefix is associated with 35 and 750 Series tooling, with 46 Series support through the PUADP1 U-die adapter. This is why the same conductor row can show both a W-style and U-style die: the tool architecture is part of the selection.
Cross-check the connector marking
Burndy says its HYDENT compression connectors are marked with wire size/type, die index and color coding, plus the proper number and location of crimps. A 6 AWG long-barrel HYLUG example is marked Blue with die index 7, matching the common U5CRT row. That connector-level marking is stronger evidence than searching a die by color alone.
U-die tool-family examples
Y46 / PAT46 + PUADP1
Burndy U-die pages document the PUADP1 adapter path for applicable 46-series tools.
Verify the other tool manufacturer
Greenlee publishes selected 12-ton competitive-die cross references. Use those explicit tables rather than assuming every U-die head supports a Burndy connection.
Why the die index can be more useful than the color
Colors repeat across different sizes and connector systems. The die index is tied to the groove/profile and is commonly embossed into the completed connector. For inspection or troubleshooting, record the connector catalog number and visible die index rather than relying on “the blue die” or “the yellow die.”
Technical sources used for this guide
- Burndy Compression Connections — Section C — master compression catalog containing the selected die-index chart summarized on this page.
- Burndy Die Index Reference — Section O — prefix/tool-family explanation and die-index reference.
- Burndy HYDENT Compression Terminals — connector marking conventions: size/type, die index, color and crimp count/location.
- Burndy U5CRT — Blue, Index 7 — example U-die product page and Y35/Y750/PAT750 tool-family applicability.
- Burndy U29RT — Yellow, Index 16 — example 250-kcmil/common U-die index row.
- Burndy U36RT — Green, Index 22 — example 600-kcmil U-die row and tool-family applicability.
- Greenlee 2025 Utility Catalog — manufacturer-published competitive 12-ton die cross-reference for selected applications.
Burndy Die Chart & Crimp Die Index Reference FAQs
What does the Burndy die index number mean?
It identifies the groove/profile assigned to the connector system. Burndy uses prefix letters and die indexes to map connector requirements to installation dies and tool families.
Is the Burndy color code enough to select a die?
No. Color is a field aid. Use the connector catalog number, conductor size/type, die catalog number and die index together.
Why are both W and U die numbers shown for some conductor sizes?
Burndy publishes different die families for different installation-tool systems. A W-die row and U-die row can correspond to the same connector/conductor size, but the tool family and approved connection instructions still control.
Can I use the table below for aluminum connectors?
No. The selected table on this page summarizes common copper lug/splice rows from the Burndy compression catalog. Aluminum and other connector families have separate tables and should not be inferred from it.
Does a Burndy U die fit Y750 tools?
Burndy U-die product pages commonly list Y35, Y750 and PAT750, with 46-series tools using the PUADP1 adapter for applicable U dies. Verify the exact die and connector instructions.