The Ellis Mini Screw Jack is the premier low-profile solution for structural support in tight spaces. Engineered for maximum durability, these adjustable steel jack posts are perfect for foundation repair, crawl space reinforcement, and leveling sagging floors where standard jacks won't fit. With a safe load capacity of 15,000 lbs and a specialized Acme screw for precision adjustments, our mini jacks provide the permanent stability required for both residential and industrial applications. Whether you are a homeowner fixing a squeaky floor or a contractor handling heavy-duty lifting, the MJ-3 and MJ-6 offer the strength of a full-sized shore in a compact, reliable design. Specifications The Ellis Mini Jacks are offered in two sizes, with minimum heights of either 6.5" (MJ-3) or 9.5" (MJ-6) and 15,000 lbs. of safe load capacity. Looking for a shorter option? Check out the STEALTH-3, STEALTH-4, and STEALTH-5 Steel Shores. Demonstration Video Specifications Ellis Mini Jack 2.5" Adj. (MJ-3) Load Capacity: 15,000 Lbs / 7.5 Tons (Includes 2.5 to 1 Factor of Safety) Overall Height Screwed Down: 6-1/2" Overall Height Fully Extended: 9" Base Plate: 4" Sq. Top Plate: 4" Sq. (Swivels Independently from Screw) Acme Screw Size: 1-1/4" Range of Adjustment: 2.5" Lifting Capacity: 3,000 LBS. w/ 12" turning bar (MJ-TB12). Safety Lock Set Screw: Included Ellis Mini Jack 5.5" Adj. (MJ-6) Load Capacity: 15,000 Lbs / 7.5 Tons (Includes 2.5 to 1 Factor of Safety) Overall Height Screwed Down: 9-1/2" Overall Height Fully Extended: 15" Base Plate: 4" Sq. Top Plate: 4" Sq. (Swivels Independently from Screw) Acme Screw Size: 1-1/4" Range of Adjustment: 5.5" Lifting Capacity: 3,000 LBS. w/ 12" turning bar (MJ-TB12). Safety Lock Set Screw: Included *Make adjustments to the height of the Mini Jack by turning the turning wheel. A 3/4" round rod can be used for extra leverage (MJ-TB12). Top plate will swivel independently from the screw. *All Load Capacities include a 2.5 to 1 Factor of Safety. Load test reports available upon request. *Mini Jacks should be attached to a flat solid foundation and should not be subject to any lateral force. Mini Jacks should be used to support straight vertical loads only. We recommend tightening set screw in the side of the 4 hole nut with 6mm allen wrench prior to loading (unless lifting). Before construction begins it is recommended that you consult with certified engineer for approval of our products within your application. Do not extend screw past advertised adjustment range. Do not exceed max safe load capacity. Shop Drawings and CAD Blocks: Item Number Shop Drawing (.PDF) AutoCAD Block (.DWG) MJ-3 MJ-3 Shop Drawing MJ-3 CAD Block coming soon MJ-6 MJ-6 Shop Drawing MJ-6 CAD Block
