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Yellow heat-shrink butt splice connector, 1.5 in long, tin-plated copper body

3M

3M MH10BCK Butt Splice Connector 10 AWG Yellow Heat Shrink

SKU CH-2T5R-Q6P54

Heat-shrink butt splice connector for 12-10 AWG wire, rated 1,000 V and 221 °F, with seamless tin-plated copper barrel

  • TypeElectrical Connectors
  • Handles 10 AWG maximum wire size
  • Heat-shrink insulation seals out moisture
  • Rated for 1,000 V maximum voltage
  • Withstands 221 °F operating temperature
  • Crimp termination with tin-plated copper barrel

Purpose and fit

The 3M MH10BCK butt splice connector joins 12 AWG to 10 AWG copper conductors with a crimp termination. Its yellow heat-shrink insulation provides a sealed, insulated joint rated for up to 1,000 volts. The seamless tin-plated copper barrel suits automotive, marine and industrial wiring where a compact, reliable splice is required.

Thermal and electrical limits

The connector carries a maximum operating temperature of 221 degrees F and meets UL, CSA and RoHS 2011/65/EU standards. Tin-plated copper contacts maintain low resistance across the joint while the heat-shrink sleeve resists moisture and abrasion in normal service conditions. No external power draw or active cooling is involved.

What the heat-shrink sleeve changes

Applying heat shrinks the yellow insulation tightly around the crimped barrel and wire insulation, creating a water-resistant seal and adding mechanical strain relief. The 1.5 inch overall length and 0.142 inch barrel inside diameter allow the sleeve to cover the connection fully without extra tubing or tape. The result is a single-piece splice that stays insulated and sealed after installation.

Highlights

  • Handles 10 AWG maximum wire size
  • Heat-shrink insulation seals out moisture
  • Rated for 1,000 V maximum voltage
  • Withstands 221 °F operating temperature
  • Crimp termination with tin-plated copper barrel

Specifications

Brand3M
TypeElectrical Connectors

Questions about this item

How do I install the 3M MH10BCK butt splice connector and which step is often done incorrectly?

Strip the wire, insert it fully into the seamless barrel until the insulation touches the barrel end, crimp with a ratchet tool calibrated for 10 AWG, then apply heat evenly until the yellow heat-shrink tubing shrinks and adhesive flows; the step most often missed is heating long enough for the adhesive to seal the connection completely.

What maintenance or replacement will the 3M MH10BCK connector need over time?

The tin-plated copper barrel and heat-shrink insulation are designed for the life of the wiring harness; no scheduled maintenance is required, but inspect for cracked tubing or corrosion after exposure to extreme vibration or temperatures above 221 Degrees F and replace the entire splice if damage is found.

What is the first limit reached when the 3M MH10BCK connector runs under sustained load?

The 221 Degrees F maximum operating temperature of the heat-shrink insulation is the first limit encountered under continuous current; exceeding it degrades the tubing seal before the tin-plated copper barrel or 1,000 V rating becomes a concern.

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