Jarvis 30-40 Series Zinc Casters and the S30-S40 Stainless variants feature a variety of attachments as shown below, and support capacities up to 325 pounds each. All swivel models feature dust cap which protects swivel raceway bearings and improves performance. Double ball bearing with hardened raceways. Includes 3/8″ diameter axle bolt with lock nut, a King Pin from 1/2″ steel rivet, hydraulically upset.

These Jarvis Casters are designed for heavy-duty applications such as food service, hospitality, and industrial settings, featuring a robust construction that ensures long-lasting reliability. With options in various sizes, materials, and finishes, these casters provide smooth, efficient mobility for large equipment, including ovens, refrigerators, and heavy carts. These casters are engineered to withstand high traffic and challenging conditions while maintaining ease of movement and safety.

Series 34 – Spring Ring Stems

A spring ring stem is used on a caster primarily for secure and easy installation into tubular furniture or equipment legs, such as chairs, carts, or shelving. Here’s why you’d use it:

• Snap-in Installation: The spring ring compresses during insertion and then expands inside the tube to hold the caster in place without the need for screws or tools.
• Firm Fit: It provides a tight, rattle-free fit that resists loosening over time, even with regular movement or vibration.
• Quick Replacement: Casters with spring ring stems are easy to remove and replace, making maintenance simple.
• Compatibility: Ideal for standard round or square tubing, especially in applications where traditional threaded or grip-ring stems aren’t suitable.

In short, a spring ring stem is a practical choice when you need a tool-free, secure, and serviceable caster installation for tubular frames.

Series 36 – Threaded Stems

A threaded stem is used on a caster when you need a strong, secure, and adjustable attachment to the equipment or furniture. Here’s why you’d choose a threaded stem:

• Secure Fit: The threads allow the caster to be tightly screwed into a pre-threaded insert or nut, ensuring a solid, wobble-free connection.
• Height Adjustability: Threaded stems can be used with locknuts or washers to allow for height adjustments or leveling of equipment.
• Heavy-Duty Use: Ideal for heavier loads or applications where strength and durability are important—such as industrial carts, machinery, or shelving.
• Versatility: Available in various thread sizes (e.g., 3/8″-16, M10), making them compatible with metal, wood, or composite bases that have corresponding inserts or mounts.
• Permanent Installation: Unlike snap-in options, a threaded stem offers a more permanent and tamper-resistant solution.

In short, a threaded stem is the go-to option when you need a durable, adjustable, and secure mounting method for demanding environments.

Series 38 – Pipe Thread Stems

A pipe thread stem (typically using NPT – National Pipe Thread) is used on a caster when you need a very strong, secure, and often semi-permanent connection—especially in industrial or heavy-duty applications. Here’s why you’d use a pipe thread stem:

• Tapered Fit for Extra Security: Pipe threads are tapered, meaning they tighten as they’re screwed in, creating a tight, secure seal that resists loosening from vibration or movement.
• Heavy-Duty Applications: Ideal for industrial carts, machinery, or equipment that carry heavy loads and require maximum durability and stability.
• Thread-Locking Capability: Often used with thread sealant or tape (like PTFE) to prevent loosening and improve the bond—helpful in environments with a lot of motion or torque.
• Permanent Mounting: Designed for more permanent installations where quick removal isn’t a priority, making them great for fixed setups.
• Compatibility with Pipe Fittings: Commonly used in setups that already use plumbing-style fittings or require mounting into metal or threaded pipe structures.

In summary, a pipe thread stem caster is best when you need maximum strength, vibration resistance, and long-term stability—especially in demanding industrial or mechanical environments.

A round stem on a caster is used when you need a simple, cost-effective mounting solution for light- to medium-duty applications, especially in furniture or equipment with compatible round holes or sleeves. Here’s why you’d use it:

• Simple Design: Round stems are easy to install, especially when used with a compression ring, friction ring, or adapter sleeve to hold the caster securely in place.
• Cost-Effective: Typically more affordable and widely available, making them a practical choice for mass-produced furniture or equipment.
• Ideal for Tubular Frames: Commonly used in chairs, light carts, racks, and displays that have round tubular legs or sockets.
• Quick Replacement: They allow for fast removal and replacement, which is helpful for maintenance or upgrades.
• Versatility with Inserts: Round stems can be paired with plastic or metal inserts that fit inside the mounting tube, increasing compatibility and stability.

In short, a round stem caster is a versatile and economical choice when mounting into round holes or sleeves is required, particularly in light-duty or office/furniture applications.

Series 30 – Plates