Backer-On No. 9 x 1-1/4 in. star drive cement board screws are purpose-built fasteners for securing cement board in moisture-prone areas like bathrooms and kitchens. These self-drilling and self-tapping screws eliminate the need for pre-drilling, saving time on installation while delivering a secure, reliable hold in cement board and similar materials.
The flat head design sits flush with the surface, leaving no protruding tip—ideal for finished applications where a smooth, professional appearance matters. With a serrated thread pattern and durable steel construction, these screws provide enhanced holding power and lasting reliability. A 185-piece pack ensures you have plenty on hand for larger projects or to keep in stock.
Features and Benefits
- Star Drive (T25): The T25 star-shaped drive ensures secure grip and reliable engagement during installation.
- Self-Drilling and Self-Tapping: Penetrate materials without pre-drilling, reducing labor time and keeping installation straightforward.
- Flat Head Design: Countersinks flush with the surface for a clean, finished look on visible installations.
- Serrated Thread Pattern: Aggressive threading improves grip and holding power in cement board and comparable materials.
- Steel Construction: Robust body provides durability for reliable fastening performance.
Specifications
- Brand: Backer-On
- Model: 23500
- Size: No. 9 x 1-1/4 in.
- Head Type: Star flat head (T25 drive)
- Thread Type: Serrated
- Pack Count: 185 pieces








