3M Scotch Super 33+ Electrical Tape - 3/4 in x 52 ft, Premium Grade All-Weather Vinyl, Resistant to Abrasion, Moisture, Corrosion, Alkalies - Black, 1 Roll

I keep a roll of Super 33+ in every kit—one in the tool bag, one in the truck, and another on the bench. It’s the electrical tape I reach for when a connection can’t fail, the weather won’t cooperate, and I don’t want to revisit the job in six months to fix a lifting tail.

What sets it apart

Super 33+ isn’t just “another black tape.” It’s a premium-grade, flame-retardant PVC with a pressure-sensitive rubber adhesive that stays workable in the cold, bonds aggressively without turning gummy in the heat, and conforms around awkward shapes without flagging. Rated up to 600 V and 221°F (105°C), it’s designed for primary insulation on splices and for harnessing—indoors, outdoors, above or below grade. It carries the certifications I look for on professional work (UL Listed, CSA, IEC 60454, VDE), and it plays nicely with both solid dielectric and synthetic cable insulations, jackets, and splicing compounds.

The headline for me is consistency. Cheaper tapes can work on perfect days; Super 33+ works on real-world days.

Handling and application

The first impression is stretch and control. The tape stretches smoothly without white-stressing or thinning out to the point of tearing, which is critical for building a uniform, moisture-tight wrap. It’s thin and supple enough to wrap tight radii—think small terminations and complex harness branches—yet it has enough body to build a protective jacket in a few passes.

A few application notes from the field:
- For primary insulation up to 600 V, I half-lap each turn to build two layers minimum, keeping light, even tension.
- I avoid stretching the last inch of the wrap to prevent tail lift. A relaxed final lay-down locks the end without needing a messy overwrap.
- For wet locations, I’ll underlay with a mastic (e.g., a butyl or rubber splicing tape) and then overwrap with Super 33+ to create a long-term moisture seal with real mechanical protection.
- On harness work, the tape’s conformability allows clean, low-bulk transitions. It doesn’t telescope on the roll or snap under tension the way bargain tapes often do.

The adhesive grabs quickly, even on cooler mornings, but you still get a few seconds to reposition. Once it’s set, it stays put.

Performance in weather and over time

I’ve used this tape on rooftop junctions, exterior sensor leads, and low-mounted fixtures exposed to snow and splash. The combination of UV resistance and a rubber adhesive that doesn’t slump in heat is what keeps these installs looking professional. After a season of sun, I don’t see the edge ooze and dust collection you get with commodity tapes. In the cold, it doesn’t shatter or lose tack the moment you tug to get around a corner.

It’s rated for 0°F to 221°F. In practical terms, I’ve applied it comfortably in the teens and seen it hold shape and adhesion through hot attic summers. That stability matters for anything that vibrates or sees mechanical stress—motors, bikes, tools, and equipment cords included.

Electrical work: from splices to harnessing

For primary insulation on 600 V class conductors, Super 33+ builds up cleanly and leaves a uniform wall without ridges or gaps. On pigtails in panels, it tucks neatly under wire nuts and maintains a tidy profile. For harnesses, it binds groups firmly without that brittle feel that leads to cracking months later.

The tape is flame-retardant and designed to inhibit conductor corrosion, which is a nice bit of insurance in damp or chemical-exposed environments. It’s also compatible with typical splicing compounds and jacket materials, so I don’t worry about odd reactions in mixed-chemistry assemblies.

Beyond electrical: practical, everyday uses

Good tape earns its keep outside electrical boxes. I’ve used Super 33+ to finish bar tape on road bikes, protect tool handles, secure temporary labels on rough plastic bins, and edge-guard gear that sees regular abrasion. It adheres to composite and rubbery surfaces better than most, and because it doesn’t ooze, it looks tidy longer. When it’s time to remove it, I can pull it up with minimal residue—assuming I didn’t over-stretch it during application.

Durability and clean removal

Over months outdoors, I’ve found the finish stays matte and intact, not chalky or brittle. If a job requires later access, the tape peels without leaving a sludge line, provided it wasn’t cooked at high tension under direct sun for a year. In harsher scenarios (salt spray, constant flex), it still outlasts general-purpose tapes by a wide margin.

Specifications that matter

• Rated for up to 600 V primary insulation
• Temperature rating: 0°F to 221°F (105°C)
• Flame-retardant; resists UV, abrasion, moisture, corrosion, alkalies, and acids
• Elastic PVC backing with an aggressive rubber-based adhesive
• Certified: UL, CSA, IEC 60454, VDE
• Size: 3/4 in x 52 ft (single roll)

The 52 ft length is worth noting. It’s shorter than some shop standards, so heavy users may want to stock a few extra rolls.

Super 33+ vs alternatives

• Against bargain electrical tapes: The difference shows up immediately in stretch control, cold-weather tack, and long-term edge integrity. Cheap tapes save money at the register and cost time on callbacks.
• Against “heavy-duty” premium tapes: Heavier tapes can add protection but at the cost of flexibility and bulk. For many tasks, Super 33+ hits the sweet spot—easy to conform, strong enough to protect, and compact.
• Within 3M’s own lineup: If you need a thicker outer jacket for abrasion or want extra insurance in high-heat, high-wear spots, step up to a heavier grade for the outer layer and keep Super 33+ as your inner wrap. For most primary insulation and harnessing, Super 33+ is the workhorse.

Limitations

• Price per roll is higher than commodity tapes. The payoff is performance and fewer rewraps.
• The 52 ft roll goes quickly on larger joints and harnesses. Plan inventory accordingly.
• For direct-bury or continuously submerged connections, you’ll still want a proper splicing system with mastic and possibly heat-shrink; Super 33+ is an overwrap in those scenarios, not the sole barrier.

Best practices for reliable wraps

• Clean the substrate: wipe off oils and dust before wrapping.
• Maintain consistent tension; don’t overstretch to the point of whitening.
• Half-lap your wraps for two layers minimum on primary insulation.
• Relax the final inch to prevent tail lift.
• For wet or corrosive locations, underwrap with a mastic and overwrap with Super 33+.
• Labeling over the tape? Use a compatible marking system or overlaminate to prevent smearing.

Value

Super 33+ isn’t the cheapest tape in the drawer, but it’s consistently cheaper than a trip back to fix a lifted edge or a cracked wrap. On professional jobs where standards and safety matter, the certifications and field behavior justify the premium. Even in the shop, the time saved on clean, first-pass wraps is tangible.

Who it’s for

• Electricians and technicians who need UL/CSA-compliant primary insulation up to 600 V
• Installers working outdoors or in temperature extremes
• Anyone doing long-lasting harnessing, equipment maintenance, or protective wraps where clean removal matters
• Power users who value consistent stretch, tack, and weather resistance

Recommendation

I recommend Super 33+ as a primary electrical tape for professional and serious DIY use where reliability, clean handling, and weather resistance matter. It stretches predictably, adheres in the cold, resists UV and abrasion, and holds up without turning into a sticky mess. The roll length is on the short side and the price is premium, but the performance and consistency more than make up for both. If you keep only one electrical tape in your kit, make it this one.