Product Description

M15 × 1.5 Titanium Hex Slotted Castle Nut

Designed for motorcycle and automotive hardware applications, this S-PARTS M15 × 1.5 titanium slotted castle nut combines a precision-machined hex body and castellated top profile with the lightweight and corrosion-resistant properties of Grade 5 titanium.

Specifications

Lightweight Titanium, High Strength-to-Weight Ratio

S-PARTS selects Grade 5 titanium alloy (Ti-6Al-4V), the internationally recognized designation corresponding to the titanium alloy commonly referred to as TC4 in China.

Working with a specialized metal material supply chain serving Xi'an's civil aerospace industry, S-PARTS applies strict material selection and laboratory comparison testing to maintain consistent material standards.

According to S-PARTS material testing, the selected titanium alloy has an average tensile strength exceeding 1,050 MPa, above the stated industry benchmark of 895 MPa.

Compared with conventional steel hardware, Grade 5 titanium offers an exceptional strength-to-weight ratio, delivering high mechanical performance at approximately half the weight of comparable steel components under comparable conditions.

For motorcycle and automotive enthusiasts looking to reduce hardware weight without giving up the advantages of a high-performance metal, titanium provides an ideal balance of strength, light weight, and corrosion resistance.

Precision Forged & CNC Machined

Each S-PARTS castle nut is formed using a custom-designed hot-forging die before precision CNC machining.

To maintain dimensional accuracy during the approximately 650°C hot-forging process, each dedicated forging die is used no more than 300 times before replacement.

The nut body is then precision-machined using S-PARTS industrial-grade multi-axis CNC equipment. Strict dimensional and thread-tolerance control helps ensure clean machining, precise thread engagement, and consistent fitment.

From the external hex profile and castellated top to the threaded section, every detail is carefully machined for a clean and refined finish.

PVD Vacuum Nitriding Finishes

Gold, Rainbow, Black, and Blue versions are finished using a PVD vacuum nitriding process.

This process creates a dense surface layer that improves surface hardness and resistance to everyday wear and impact while producing a vivid metallic finish.

Unlike conventional paint, the PVD-treated surface is designed for better durability during regular use, helping maintain its appearance through exposure to moisture, road grime, and everyday riding conditions.

Electrochemically Anodized Titanium Finishes

Green, Purple, and Candy versions use an electrochemical anodizing process.

Rather than relying on conventional dyes, anodizing creates a controlled oxide layer on the titanium surface. The thickness of this oxide layer affects how light is reflected and refracted, producing the distinctive colors characteristic of anodized titanium.

The Candy finish has especially dynamic color variation. Because the final appearance depends on the anodizing process and oxide-layer characteristics, the color distribution is naturally varied and each piece may have its own unique color pattern.

Candy Color Notice: Due to the nature of the anodizing process, Candy colors are highly variable and may differ from the product images. Each piece has a unique and naturally flowing color pattern.

Thread Color Notice: Some pieces may have light-colored lines or marks around the threaded area. This is a normal result of the coloring process and does not affect normal use.

Key Features

• M15 × 1.5 precision thread
• 19 mm overall height
• 24 mm socket wrench size
• Approx. 22.7 g per piece
• Made from Grade 5 Titanium (Ti-6Al-4V)
• Hex body with slotted/castellated top
• High strength-to-weight ratio
• Excellent corrosion resistance
• Precision hot-forged and CNC machined
• Multiple PVD and anodized color options
• Designed for motorcycle and automotive hardware applications

Installation Note

Please verify the thread size, pitch, dimensions, and application requirements before purchase.

For installation, use the appropriate 24 mm socket wrench and follow the recommended torque specifications for your specific vehicle or component. For safety-critical applications, always follow the vehicle or component manufacturer's installation requirements.