The NATIONAL Oil Seal 2.250x4.010x0.813 M/L/L Leather is designed for industrial rotating equipment requiring robust construction, dependable lubricant retention, and good adaptability to worn or slightly irregular shaft surfaces.

The manufacturer-specific M/L/L Profile indicates a composite seal construction involving a metal supporting structure and multiple leather sealing elements or sections. The metal component helps maintain dimensional stability and secure installation within the housing, while the leather sealing surfaces create controlled contact around the rotating shaft.

Because M/L/L profile codes are manufacturer-specific, the exact number of leather lips, lip orientation, spacing between sealing elements, outside-case configuration, internal reinforcement, and installation direction should be verified against the original seal or technical drawing before replacement.

Genuine industrial leather can absorb a small amount of lubricant and maintain a thin lubricating film at the shaft-contact area. Under suitable operating conditions, this characteristic helps reduce dry friction and supports stable sealing performance.

Leather sealing elements can also conform to minor shaft wear and moderate surface irregularities. This makes the seal particularly suitable for older machinery, rebuilt equipment, and restoration applications where preserving the original sealing arrangement is important.

The relatively wide 0.813-inch axial section suggests a substantial or multi-element seal construction intended for a dedicated housing rather than a conventional narrow oil-seal groove.

The seal is generally suitable for compatible applications involving:

• Mineral oils
• Gear oils
• Bearing grease
• Industrial lubricating oils
• Petroleum-based lubricants
• Compatible grease-lubricated systems

Leather performance depends on leather grade, lubricant type, shaft speed, operating temperature, moisture exposure, shaft condition, and environmental conditions. These factors should be confirmed before installation.

The inch dimensions correspond approximately to:

Shaft diameter: 2.250 inches or 57.15 mm

Housing diameter: 4.010 inches or 101.85 mm

Seal width: 0.813 inch or 20.65 mm

The relatively large housing diameter and wide axial section indicate that this seal may be intended for a dedicated gearbox, bearing housing, transmission, axle assembly, or OEM industrial machine. Accurate dimensional measurement and full M/L/L profile verification are essential before replacement.

⚙️ Applications

• Industrial gearboxes
• Bearing housings
• Mechanical transmissions
• Agricultural machinery
• Construction equipment
• Mining and quarry machinery
• Conveyor drive assemblies
• Power transmission systems
• Legacy industrial machinery
• OEM rotating equipment

🎯 Benefits

✔ Genuine industrial leather sealing material

✔ Multi-element heavy-duty sealing arrangement

✔ Helps retain oil and compatible grease

✔ Conforms to slightly worn shaft surfaces

✔ Metal support provides dimensional stability

✔ Suitable for dusty and abrasive environments

✔ Wide construction for dedicated industrial housings

✔ Ideal for overhaul and restoration work

✔ OEM replacement ready when dimensions and profile match

🧠 Technical Insight

• NATIONAL M/L/L Seal Reference
• Metal + Leather + Leather Profile Designation
• Oil-Treated Industrial Leather Elements
• Wide Multi-Element Seal Construction
• Low-Pressure Lubricant Retention
• Good Shaft-Surface Conformability
• 57.15 mm Shaft Diameter
• Full M/L/L Cross-Section Verification Required

✅ Key Features

• NATIONAL Industrial Quality
• M/L/L Leather Profile
• Industrial Leather Sealing Arrangement
• Metal-Supported Construction
• Springless Construction Unless Otherwise Specified
• Heavy-Duty Inch-Size Design
• Industrial Replacement Seal
• OEM Cross-Reference Ready

📊 Specifications

Brand: NATIONAL

Model: M/L/L

Size: 2.250 × 4.010 × 0.813 inch

Metric Equivalent: Approximately 57.15 × 101.85 × 20.65 mm

Type: Heavy-Duty Leather Rotary Shaft Oil Seal

Sealing Material: Genuine Oil-Treated Industrial Leather

Support Material: Metal

Profile: M/L/L

Construction: Manufacturer-Specific Metal-Supported Multi-Element Leather Seal Construction

Lip Design: Multiple leather sealing elements or sections; verify against the original profile

Dust Lip: Verify from the actual M/L/L cross-section

Spring Type: Typically none; verify from the original construction

Shaft Diameter (ID): 2.250 inches / 57.15 mm

Housing Diameter (OD): 4.010 inches / approximately 101.85 mm

Width: 0.813 inch / approximately 20.65 mm

Pressure Capability: Low-pressure lubricant-retention service unless otherwise specified

Lubrication: Mineral oil, gear oil, and compatible grease

Temperature Range: Depends on the leather grade, lubricant, shaft speed, moisture exposure, and operating conditions

Application Class: Heavy-Duty Industrial and Legacy Equipment

Standard: Inch-Size Industrial Seal

🔁 Equivalent

Suitable replacement for compatible:

• NATIONAL M/L/L Leather Rotary Shaft Seal
• 2.250x4.010x0.813 Leather Oil Seal
• 57.15x101.85x20.65 Rotary Seal
• Multi-Element Leather Oil Seal
• Heavy-Duty Bearing Housing Seal
• Industrial Gearbox Leather Seal
• Transmission Leather Shaft Seal
• Legacy Equipment Leather Seal
• OEM M/L/L Shaft Seal
• Industrial Leather Rotary Shaft Seal

The same dimensions alone do not guarantee interchangeability. The replacement must match the original M/L/L cross-section, number and orientation of leather sealing elements, outside-case configuration, internal reinforcement, installation direction, and lubricant compatibility.

(Always verify dimensions, M/L/L profile geometry, leather grade, lip arrangement, shaft and housing condition, lubricant compatibility, rotational speed, temperature, and operating conditions before ordering.)

📦 Availability

✅ In Stock

🚚 Fast Delivery Available

🌎 Worldwide Shipping Available

📦 MOQ: 1 Piece

🏭 Suitable for gearbox overhaul, bearing-housing maintenance, transmission servicing, agricultural and construction machinery repair, mining equipment maintenance, legacy machinery restoration, and compatible OEM replacement applications.

📲 Contact via LINE ID: dusitrea

📧 Email: sales@seal4go.com

💬 Technical support available before ordering

🔍 Assistance available for cross-reference and equivalent part identification