C-clamp style compressor will fit most heads including Hemi. Spring cup will fit stock springs up to 1.750 Inch diameter and has a 1.100 Inch working window for access to keepers, which may be too large for some small diameter spring/retainer combinations. Compressor has 9/16 Inch hex for use with a wrench, ratchet or impact. This tool will handle spring pressures in excess of 1200 lbs. without slipping off. Details: Finish: Zinc Oxide Size: Fits Springs Up To 1.750 Inch Diameter Capacity: In Excess Of 1200 lb Spring Pressure Material: Steel Sold As: Each Product Description: Valve Spring Compressor Head-Off Steel Zinc Oxide Sold Individually Specialty items for the Shop, Trailer and Track. The Allstar Performance brand offers thousands of hard-to-find, specialty items that cover many segments in the performance aftermarket. For over 30 years, customers worldwide have come to rely on the quality, affordable and practical items available from Allstar Performance.