The only difference between Makita SP6000J and SP6000J1 is that the SP6000J1 comes with a 55-inch Guide Rail. The rail part number is 194368-5, commonly costs over $70. Thus, the SP6000J1 is more expensive than the SP6000J.

SP6000J or SP6000J1 which one to buy?
If the 55-inch track is too long or too short for your projects, you can buy the cheaper SP6000J, then use the savings to buy a shorter Makita 39-inch track(part number is 199140-0) or a longer 118-inch track (part number is 194367-7).
Otherwise,just purchase the SP6000J1.

The Guide Rails interact with the saw to provide smooth, dead-on straight cuts. Good for ripping sheet material.
Brand | Makita | Makita |
Model | SP6000J1 | SP6000J |
Type | Plunge Circular Saw | Plunge Circular Saw |
Weight | 16.5 lbs. | 9.7 lbs. |
Dimensions | 13-3/8″ x 8-7/8″ x 9-7/8″(L x W x H) | 13-3/8″ x 8-7/8″ x 9-7/8″(L x W x H) |
Power Source | Corded | Corded |
Cord Length | 8.2ft / 2.5m | 8.2ft / 2.5m |
Amp | 12 amps | 12 amps |
Volt | 120v | 120v |
Speed | 2,000 – 5,200 RPM | 2,000 – 5,200 RPM |
Arbor Size | 13/16″ (20mm) | 13/16″ (20mm) |
Blade Diameter | 6-1/2″ | 6-1/2″ |
Blade Location | Right | Right |
Bevel Capacity | 48 degrees | 48 degrees |
Bevel Stops | 22.5 degrees and 45 degrees | 22.5 degrees and 45 degrees |
Laser Guide | ||
Cutting Depth Capacity | 2-3/16″ at 90 degrees and 1-9/16″ at 45 degrees | 2-3/16″ at 90 degrees and 1-9/16″ at 45 degrees |
Adjustable Cutting Depth | Yes | Yes |
Spindle Lock | ||
Electric Brake | ||
Dust Collection | dust port directs material away from the operator and connects to a vacuum system | dust port directs material away from the operator and connects to a vacuum system |
Dust Blower | ||
Case | Yes | Yes |
Material | Magnesium components Rubberized handles Carbide Tipped blade | Magnesium components Rubberized handles Carbide Tipped blade |
Uses | Ideal for cutting large wood panels and other wood materials in confined areas | Ideal for cutting large wood panels and other wood materials in confined areas |
Includes | Makita SP6000J1 6-1/2-Inch Plunge Circular Saw 48T carbide-tipped blade wrench Tool Case and 55″ Guide Rail | Makita SP6000J 6-1/2-Inch Plunge Circular Saw, 48T carbide-tipped blade wrench stackable tool case. |
Color | Teal, black | Teal, black |
Warranty | 1 year limited warranty | 1 year limited warranty |
Manual | http://cdn.makita.com/apps/cms/doc/prod/SP6/aca2f80e-96f5-4d9c-b34f-3b438700c728_SP6000J1_IM.pdf | http://cdn.makita.com/apps/cms/doc/prod/SP6/60a3fb77-ed0e-48e3-a43b-02d5a4e2ec44_SP6000J_IM.pdf |
Misc | Variable speed control Built-in current limiter helps prevent motor burnout 1,800 Watts Out | Variable speed control Built-in current limiter helps prevent motor burnout 1,800 Watts Out |
Price | Check Price at Amazon | Check Price at Amazon |