# Seismic - 78.5mm DELTA

**Spec:**  
Diameter: 78.5mm  
Width: 68mm  
Durometer: 73.5a, 75.5a  
Contact Patch: 68mm  
Lip Profile: Square/Sharp  
Core Placement: Offset  
Wheel Surface: Smooth

**78.5mm tall x 68mm wide DELTA Wheels poured in G-LOC urethane  
**_46mm x 44mm **FUSION**_ _hub • Bearing seat offset 6.5% • 67.5mm running surface • Square outside edge, straight-cut inside edge • 9.25 oz. each_ • _Sold in sets of FOUR wheels  
_

_**Next-level traction and world’s most progressive hub-and-wheel engineering!**_  
• Revolutionary grip to hold even the most extreme lines at top velocity! Size, speed, and momentum to beat the pack on straightaways.  
• Width and offset finely-calibrated for elite racing. Lips meticulously profiled for cutting-edge balance of robust support and functional flex. Subtle 0.5mm concave running surface preloads edges, strengthens rebound, and sharpens in-slide feedback.  
• Superior grip and energy return when g-forces load up to peak intensity. Unparalleled braking, snappy pre-drifts, predictable slide release and hookup. Quick acceleration, nimble edge-to-edge response.  
• Hub structure ingeniously sculpted for highly-optimized routing of wheel rebound energy.  
• The grippiest race urethane ever seen in skateboarding, bar none.  
• Named after the Greek letter “delta” (∆), used in science to represent _change_.

_**Poured in G-LOC™ – a pivotal breakthrough in race urethane formulation!**_  
• The first significant new race compound developed since the advent of Seismic Defcon™!  
• Astonishing grip and braking power with explosive roll speed.  
• Directional slide.  
• Slow, consistent wear and exceptional durability.  
• Available in two finely-tuned durometers, both with extremely consistent, predictable handling…  
_– 73.5A Yellow:_ Fast, plush, _insanely_ grippy, and lively underfoot. Aggressive slide characteristics with extreme braking power. Superior performance on the fastest, most technical courses.  
_– 75.5A Green:_ Ideal for smoother surfaces and lighter riders. Very fast roll with friendlier slide characteristics. Exceptional grip and excellent durability.

_**The FUSION™ core**_  
• Integrates nearly 20 years of advanced hub R&D.  
• 46mm tall x 44mm wide – the largest and most supportive hub ever seen in a wheel this size_.  
_• Formed from tough, 75D fiber-reinforced Impulse Blend™ – a proprietary new hub material with next-level energy return!  
• Eight (8) contoured crossbeams (hollowed-out for lightness and aesthetics) combine with deep, wide “saddle” profile to create robust edge support and ironclad 3D mechanical lock with urethane.  
• Central crossbeams act as internal “turbine blades” that continuously catch and guide G-LOC’s superior rolling rebound energy with perfect balance and revolutionary efficiency.  _Boosts both speed and acceleration to another level!_  
• Stiff saddle walls trap and return lateral wheel flex energy to supercharge rebound out of pumps, carves, and hard corners.

## Details

- **Price:** 948.0 HKD
- **Vendor:** Seismic
- **Type:** Wheels
- **Tags:** 73.5a, 75.5a, 78.5mm, Downhill Wheels, Seismic, Sharp&Square, Ungrounded, Wheels

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| 73.5a (Yellow) | 948.00 HKD | In stock |
| 75.5a (Green) | 948.00 HKD | In stock |

## Images

- Seismic - 78.5mm DELTA
- Seismic - 78.5mm DELTA
- Seismic - 78.5mm DELTA
- Seismic - 78.5mm DELTA
- Seismic - 78.5mm DELTA

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> Source: [SBDW Longboards Hong Kong](https://sbdwlongboards.com/products/seismic-78-5mm-delta)
> Updated: 2026-04-20