/ Precision Measuring Tools / Precision Hand Tools / Precision Shop Tools / Jack Screws / 191B * Not actual product image 191B Little Giant Jack Screw - 1" Extension Base Only 50689 191 “Little Giant” Jack Screws and Sets Little Giant Jack Screw Base Extension, 1" (25mm) Base Little Giant Jack Screws are used for leveling work on planer beds, drills, setting up machinery, and general use in toolrooms or machine shops. 191 Series are 1-1/2" to 2-1/4" / 38-57mm in Size. Series 190 and 191 have 20-pitch screws and for those who desire a finer adjustment, the F190 has a 40-pitch screw. 1" Extension Base Only. Specifications 3D CAD Files / Exploded Parts Diagram Product Testimonials California Prop 65 Other similar products 191A Little Giant Jack Screw - Jack Only 191B Little Giant Jack Screw - 1" Extension Base Only 191C Little Giant Jack Screw - 1/2" Extension Base Only 191D Little Giant Jack Screw - Auxiliary Pointed Screw Only 191E Little Giant Jack Screw - Extension Base Only 191F Little Giant Jack Screw- Extension V Base Only S191 Little Giant Jack Screw Set Complete with All Attachments Contact Starrett Specifications Made in America: Yes 3D CAD Files / Exploded Parts Diagram Login to see related product files. Or create an account. Product Testimonials Write a product review Write a product review Comments* First Name* Last Name* Email* Occupation The information you provide will be used in accordance with the terms of our privacy policy. I agree to the privacy policy. Please provide the required information. Thank you for submitting a product testimonial on www.starrett.com. By submitting information to Starrett, you acknowledge and give express permission for the L.S. Starrett Company to use and share your statements. California Proposition 65 Warning WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer, and birth defects or other reproductive harm. For more information go to: www.P65Warnings.ca.gov