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Clear plastic bag holding 400 black heat-shrink butt splice sleeves

Sopoby Solder Seal Wire Connectors 400PCS Black

SKU CH-8SD9-633VM

400-piece solder-seal butt connectors with dual-wall polyolefin tubing and hot-melt adhesive create waterproof, vibration-resistant splices that shrink at 80 °C and fully melt at 138 °C

  • Product colorBlack
  • Waterproof seal from dual-walled polyolefin tubing with hot-melt adhesive
  • Permanent solder joint forms at 111 °C and fully melts at 138 °C
  • Tubing shrinks at 80 °C for tight insulation and strain relief
  • Resists abrasion, vibration and stretching in harsh environments
  • 400 pieces cover automotive, marine, RV and holiday-light wiring jobs

400-piece solder-seal connector kit

This 400-piece kit supplies black heat-shrink butt connectors with an internal solder ring and dual-walled tubing. It is aimed at automotive, marine and outdoor wiring jobs where a waterproof, vibration-resistant joint is required.

Replaces crimp-only or tape-sealed splices

Unlike plain crimp terminals, the solder ring melts at 111 and flows fully by 138, while the adhesive-lined polyolefin shrinks from 80 to form a sealed joint. The jump is worth it when the installation must survive immersion, engine vibration or repeated flexing without corrosion.

Install with a 1500 W heat gun set to 400-600

Strip the wires, slide the sleeve on, then apply hot air until the tubing shrinks and the solder ring disappears. The most common error is stopping heat too early, leaving the solder solid and the adhesive inactive, which defeats the waterproof seal.

How it compares

Measured against everything we stock in Wire Connectors & Cable Ties, at today’s prices. Recalculated every night.

Price $37.99
Pricier than about 82% of the 1,040 comparable items (median $13.99).

Specifications

Product
Product colorBlack

Questions about this item

What wire-gauge range does the black 2:1 shrink-ratio tubing cover?

The connectors use a 2:1 shrinkage ratio; the polyolefin tubing shrinks from 80 °C and the hot-melt adhesive inside forms a waterproof seal once fully recovered.

At what temperature does the internal solder ring melt completely during installation?

The solder ring begins to melt at 111 °C and is fully molten at 138 °C; apply a 1500 W heat gun set between 400 °C and 600 °C (752–1112 °F) until the solder flows through the stripped wires.

How can I tell when a crimped joint needs to be redone because the adhesive seal has failed?

If the dual-walled tubing no longer resists abrasion, stretch or vibration, or if moisture reaches the tin barrel causing corrosion, the waterproof adhesive bond has broken and the splice must be replaced.

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