Specifications: Brand: Alpha Rider Conditions: Brand New Type: Crankshaft Drilling Fixture Balancer bolt tool Material: High quality and durable Color: as pictures shown Qty: 3 pcs/set Warranty: 1 Year Package Included: 3 pcs/set Crankshaft Drilling Fixture Balancer bolt tool Fitments: For Chevy inline 6 194 230 250 For Chevy 348, 409 For SBC 265,283 and 327 and all small block Chevy For Chevy inline 216, 235 and 261 For GMC 248,270,302 For Chevy 153 4 Cyl also as used in Mercruiser and ChevyII . Features: The cranks are not drilled from the factory and adding the 7/16 bolt hole will aid you on installation of the balancer and retention of it. Much better than hitting it on with a hammer. Precision made to fit on the end of the crank. Crank key remains installed. The fillings drop out the side while drilling. A hardened drill bushing is used for perfect alignment of the drill during drilling. Procedure can be done in chassis You may need to lift engine for drill clearance. This procedure can be performed on a assembled engine. The tool will fit on the snout. Be sure to plug the seal hole with a rag and direct the slot to the down position for chip discharge. 7/16-20 tap and proper drill bit are included. Drill 1.75 deep. This tool is used to drill a perfectly centered hole in the tip of the crank to be tapped for a harmonic balancer bolt. Fit For 283-327 Chevy Inlines 235-261 194 230 250. Can be done to a assembled engine, just align the discharge slot oriented down for the shavings. This is for a 7/16-20 thread. A precision drill bushing is used to align the drill. NOTE: 1.Due to the light and screen difference, the item’s color may be slightly different from the pictures. 2.All dimensions are measured by hand, there may be small deviations. 3.This Is Aftermarket Replacement Item. 4.Please check your correct replacement parts before purchase, the picture show more detail, thank you. On Nov 28, 2023 at 04:22:04 PST, seller added the following information: