# Twin Power 70-E79 FL FX 71-79 XL Advance Unit Screw Replaces H-D 3570

Twin Power™ advance unit screw precisely replaces H-D 3570, securing the timer assembly for accurate ignition timing on 1970-early 1979 FL/FX Big Twins and 1971-1979 XL Sportsters.

-   Direct OEM replacement ensures stable advance mechanism operation during distributor service
-   High-quality steel construction resists vibration and wear in Shovelhead-era engines
-   Essential hardware for complete ignition rebuilds or points conversions

This Part Fits:

Year

Make

Model

Submodel

1971-1979

Harley-Davidson

FLH Electra Glide

Base

1971-1978

Harley-Davidson

FX Super Glide

Base

1974-1979

Harley-Davidson

FXE Super Glide

Base

1979

Harley-Davidson

FXEF Fat Bob

Base

1977-1979

Harley-Davidson

FXS Low Rider

Base

1971-1979

Harley-Davidson

XLCH

Base

1977-1978

Harley-Davidson

XLCR Cafe Racer

Base

1978-1979

Harley-Davidson

XLS Roadster

Base

1977-1978

Harley-Davidson

XLT

Base

## Details

- **Price:** 26.92 CAD
- **Vendor:** TwinPower
- **Type:** Distributors

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 26.92 CAD | In stock |

## Images

- Photo - Primary

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> Source: [Standard Auto Part](https://www.standardautopart.com/products/twin-power-70-e79-fl-fx-71-79-xl-advance-unit-screw-replaces-h-d-3570)
> Updated: 2026-07-14