The Genie 991690GT is a genuine OEM Star Lock Washer, 3/8 designed for Genie AL series portable light towers, including the AL4, AL4L, AL4000, AL5, AL5L, AL5HT, AL5000, and AL5 with Vertical Mast. As a factory-original component, this washer is manufactured to the same tolerances and material specifications as the part it replaces, ensuring a correct, consistent installation every time. Cross-reference part number 991690GT against your machine's parts manual to confirm fitment before ordering. Keeping genuine hardware on hand means your light tower stays properly fastened and ready when the job demands it.
Key Features
- Genuine OEM Hardware Grade — Manufactured to Genie's original material and hardness specifications, so the star teeth bite and hold the way they were engineered to from day one.
- Direct-Fit Installation — This washer seats onto 3/8 fasteners exactly as the original, requiring no trimming, filing, or adaptation during reassembly.
- Broad AL Series Coverage — Fits the AL4, AL4L, AL4000, AL5, AL5L, AL5HT, AL5000, and AL5 with Vertical Mast — one part number covering the core Genie portable light tower lineup.
- Vibration-Resistant Locking Action — The star serrations grip mating surfaces under load, resisting loosening from engine vibration and road travel between jobsites.
- Structural Integrity Where It Counts — On a light tower, fastener security directly affects the stability of the mast, generator housing, and outrigger connections — using the correct locking hardware is not optional.
A star lock washer works by pressing its serrated teeth into the bearing surfaces of both the fastener head and the mating component. As the bolt or nut is tightened, those teeth bite in and create mechanical resistance against rotation, preventing the fastener from backing out under vibration or repeated loading. On a portable light tower like the Genie AL series — which regularly experiences engine vibration during operation and road stress during transport — this locking action is essential for keeping structural and mechanical connections secure. A worn or missing lock washer allows fasteners to loosen gradually, which can compromise mast stability, panel alignment, or generator mounting over time.
Part Details
| Part Number | 991690GT |
|---|---|
| Brand | Genie |
| Part Type | Genuine OEM |
| Description | Star Lock Washer, 3/8 |
Compatibility & Fitment
| Name | Model |
|---|---|
| AL4000 | AL4000 |
| AL5000 | AL5000 |
| AL5 with Vertical Mast | AL5 with Vertical Mast |
| AL4 | AL4 |
| AL5 | AL5 |
| AL4L | AL4L |
| AL5L | AL5L |
| AL5HT | AL5HT |
Verify Before You Order
Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.
Why Buy From DHS Equipment
Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.
Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.
