6704-2RS Rubber Sealed Thin Section Deep Groove Ball Bearing | 20×27×4 mm

The 674 Open is a precision-engineered, single-row miniature ball bearing designed for applications where absolute minimal rotational resistance and maximum speed are the primary requirements. By removing the physical barriers of shields or seals, this 4x7x2.5 mm component allows for unrestricted lubrication flow and zero "drag," making it perfect for high-frequency vibration tools and precision instruments. With a featherweight mass of just 0.3 grams, the 674 open type excels in energy-sensitive systems where reducing mechanical friction is critical to extending battery life and improving motor response.

The 672 Open is an elite-grade micro-miniature ball bearing designed for applications where spatial constraints are extreme and rotational mass must be kept to an absolute minimum. As an unshielded, open-type component, this 2×5×1.5 mm bearing provides a "zero-drag" environment, allowing for instantaneous acceleration and high-frequency oscillation. Weighing approximately 0.1 grams, the 672 is the preferred choice for high-precision laboratory instrumentation, micro-optics, and nano-robotics where the slightest mechanical resistance can compromise system accuracy.

The 679-ZZ is a specialized thin-section miniature ball bearing designed for high-precision assemblies where radial space is limited but high performance is essential. Featuring dual non-contact metal shields (ZZ), this 9×14×4.5 mm component excels in reducing rotational friction while maintaining a streamlined profile. The rigid steel shields effectively prevent the ingress of dry contaminants and ensure that the high-speed internal lubrication remains distributed across the raceways, making it an ideal choice for compact motors and sensitive electronic devices.

The 679 Open is a precision-engineered, ultra-thin miniature ball bearing designed for high-velocity applications where rotational resistance must be kept to an absolute minimum. With a 9mm bore and a slim 14mm outer diameter, this "Open" type bearing features no seals or shields, allowing for the lowest possible starting torque and unrestricted rotational flow. This design is specifically intended for use in clean, controlled environments or within enclosed housings where external lubrication—such as oil baths or mist—is readily available to maintain the bearing’s internal components.

The 678-ZZ is a high-performance, thin-section miniature ball bearing designed for advanced mechanical systems where every millimeter of space is critical. Featuring dual-side metal shields (ZZ), this 8×12×3.5 mm component provides a streamlined solution for high-density layouts. The non-contact steel shields are engineered to repel dust and dry contaminants while maintaining an ultra-low friction profile. This allows the internal factory-set lubrication to operate efficiently, ensuring long-term reliability and smooth rotation in sensitive electronic and robotic assemblies.

The 678 Open is a high-precision, ultra-thin miniature ball bearing engineered for technical applications where minimizing rotational friction is the top priority. Featuring an 8mm bore and a compact 12mm outer diameter, this "Open" configuration lacks physical seals or shields, allowing the rolling elements to rotate with nearly zero starting torque. It is the ideal choice for high-speed systems operating within enclosed, debris-free environments—such as oil-mist lubricated housings or hermetically sealed instruments—where maximum mechanical efficiency and rapid heat dissipation are required.

The 677-ZZ is a high-precision, thin-walled miniature bearing engineered for applications that require a larger shaft diameter within a restricted outer housing. Equipped with dual metal shields (ZZ), this 7×11×3 mm component provides a reliable barrier against dry contaminants without sacrificing rotational speed. The non-contact design of the steel shields ensures that the bearing maintains ultra-low starting torque, making it an essential part for battery-sensitive devices and high-frequency micro-motors where thermal management and energy efficiency are paramount.

The 6702-ZZ is a specialized, ultra-lightweight deep groove ball bearing engineered for modern applications that demand minimal spatial footprint and maximum rotational efficiency. Featuring dual non-contact metal shields (ZZ), this model effectively retains premium factory grease while delivering significantly lower rotational friction than standard rubber-sealed variants. Measuring 15mm on the bore, an outer diameter of 21mm, and a remarkably slim 4mm width, the 6702-ZZ is an essential component for UAV mechanisms, gimbal stabilizers, and sophisticated medical devices where consistent, low-torque operation is critical.