/ Precision Measuring Tools / Precision Hand Tools / Hardness & Surface Roughness Testers / Hardness Tester Accessories / PT05251 * Not actual product image PT05251 1/4" (6.4mm) Ball Unit 67950 3814, 3815, 3816, 3817 - Accessories 1/4" (6.4mm)Ball Unit Penetrator - for use with Starrett Bench Top Hardness Testers, Penetrator 1/4" Ball unit Features Specifications Downloads Product Testimonials Other similar products PT05050 Hardness Test Block Rockwell C Scale, Approximate Value 63, Material: Steel, For use with Diamond Penetrator PT05051 Hardness Test Block Rockwell C Scale, Approximate Value 60, Material: Steel, For use with Diamond Penetrator PT05052 Hardness Test Block Rockwell C Scale, Approximate Value 55, Material: Steel, For use with Diamond Penetrator PT05053 Hardness Test Block Rockwell C Scale, Approximate Value 50, Material: Steel, For use with Diamond Penetrator PT05054 Hardness Test Block Rockwell C Scale, Approximate Value 45, Material: Steel, For use with Diamond 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Scale, Approximate Value 50, Material: Steel, For use with 1/16" Ball Penetrator PT05064 Hardness Test Block Rockwell B Scale, Approximate Value 40, Material: Steel, For use with 1/16" Ball Penetrator PT05065 Hardness Test Block Rockwell B Scale, Approximate Value 30, Material: Steel, For use with 1/16" Ball Penetrator PT05067 Hardness Test Block Rockwell B Scale, Approximate Value 20, Material: Steel, For use with 1/16" Ball Penetrator PT05068 Hardness Test Block Rockwell B Scale, Approximate Value 10, Material: Steel, For use with 1/16" Ball Penetrator PT05069 Hardness Test Block Rockwell A Scale, Approximate Value 80, Material: Steel, For use with Diamond Penetrator PT05091 Hardness Test Block Rockwell A Scale, Approximate Value 70, Material: Steel, For use with Diamond Penetrator PT05092 Hardness Test Block Rockwell A Scale, Approximate Value 60, Material: Steel, For use with Diamond Penetrator PT05100 Hardness Test Block Rockwell F Scale, Approximate Value 100, Material: Brass, For use with 1/16" Ball Penetrator PT05101 Hardness Test Block Rockwell F Scale, Approximate Value 90, Material: Brass, For use with 1/16" Ball Penetrator PT05102 Hardness Test Block Rockwell F Scale, Approximate Value 80, Material: Brass, For use with 1/16" Ball Penetrator PT05103 Hardness Test Block Rockwell F Scale, Approximate Value 70, Material: Brass, For use with 1/16" Ball Penetrator PT05104 Hardness Test Block Rockwell F Scale, Approximate Value 60, Material: Brass, For use with 1/16" Ball Penetrator PT05105 Hardness Test Block Rockwell F Scale, Approximate Value 50, Material: Brass, For use with 1/16" Ball Penetrator PT05106 Hardness Test Block Rockwell E Scale, Approximate Value 100, Material: Brass, For use with 1/8" Ball Penetrator PT05107 Hardness Test Block Rockwell E Scale, Approximate Value 90, Material: Brass, For use with 1/8" Ball Penetrator PT05108 Hardness Test Block Rockwell E Scale, Approximate Value 80, Material: Brass, For use with 1/8" Ball Penetrator PT05112 Hardness Test Block Rockwell E Scale, Approximate Value 70, Material: Brass, For use with 1/8" Ball Penetrator PT05113 Hardness Test Block Rockwell E Scale, Approximate Value 60, Material: Brass, For use with 1/8" Ball Penetrator PT05114 Hardness Test Block Rockwell E Scale, Approximate Value 50, Material: Brass, For use with 1/8" Ball Penetrator PT05115 Hardness Test Block Superficial Rockwell Scale 30N, Approximate Value 80, Material: Steel, For use with Diamond Penetrator PT05122 Hardness Test Block Superficial Rockwell Scale 30N, Approximate Value 70, Material: Steel, For use with Diamond Penetrator PT05123 Hardness Test Block Superficial Rockwell Scale 30N, Approximate Value 60, Material: Steel, For use with Diamond Penetrator PT05124 Hardness Test Block Superficial Rockwell Scale 30N, Approximate Value 50, Material: Steel, For use with Diamond Penetrator PT05125 Hardness Test Block Superficial Rockwell Scale 30N, Approximate Value 40, Material: Steel, For use with Diamond Penetrator PT05127 Hardness Test Block Superficial Rockwell Scale 30T, Approximate Value 80, Material: Brass, For use with 1/16" Ball Penetrator PT05128 Hardness Test Block Superficial Rockwell Scale 30T, Approximate Value 70, Material: Brass, For use with 1/16" Ball Penetrator PT05129 Hardness Test Block Superficial Rockwell Scale 30T, Approximate Value 60, Material: Brass, For use with 1/16" Ball Penetrator PT05130 Hardness Test Block Superficial Rockwell Scale 30T, Approximate Value 50, Material: Brass, For use with 1/16" Ball Penetrator PT05177 Hardness Test Block Superficial Rockwell Scale 30T, Approximate Value 40, Material: Brass, For use with 1/16" Ball Penetrator PT05178 Hardness Test Block Superficial Rockwell Scale 30T, Approximate Value 30, Material: Brass, For use with 1/16" Ball Penetrator PT05179 Hardness Test Block Superficial Rockwell Scale 30T, Approximate Value 20, Material: Brass, For use with 1/16" Ball Penetrator PT05180 Hardness Test Block Superficial Rockwell Scale 30T, Approximate Value 10, Material: Brass, For use with 1/16" Ball Penetrator PT05181 Hardness Test Block Superficial Rockwell Scale 15N, Approximate Value 90, Material: Steel, For use with Diamond Penetrator PT05182 Hardness Test Block Superficial Rockwell Scale 15N, Approximate Value 80, Material: Steel, For use with Diamond Penetrator PT05183 Hardness Test Block Superficial Rockwell Scale 15N, Approximate Value 70, Material: Steel, For use with Diamond Penetrator PT05184 Hardness Test Block Superficial Rockwell Scale 15T, Approximate Value 90, Material: Brass, For use with 1/16" Ball Penetrator PT05185 Hardness Test Block Superficial Rockwell Scale 15T, Approximate Value 80, Material: Brass, For use with 1/16" Ball Penetrator PT05186 Hardness Test Block Superficial Rockwell Scale 15T, Approximate Value 70, Material: Brass, For use with 1/16" Ball Penetrator PT05187 Hardness Test Block Superficial Rockwell Scale 15T, Approximate Value 60, Material: Brass, For use with 1/16" Ball Penetrator PT05188 Hardness Test Block Superficial Rockwell Scale 45T, Approximate Value 70, Material: Brass, For use with 1/16" Ball Penetrator PT05189 Hardness Test Block Superficial Rockwell Scale 45T, Approximate Value 60, Material: Brass, For use with 1/16" Ball Penetrator PT05191 Hardness Test Block Superficial Rockwell Scale 45T, Approximate Value 50, Material: Brass, For use with 1/16" Ball Penetrator PT05192 Hardness Test Block Superficial Rockwell Scale 45T, Approximate Value 40, Material: Brass, For use with 1/16" Ball Penetrator PT05193 Hardness Test Block Superficial Rockwell Scale 45T, Approximate Value 20, Material: Brass, For use with 1/16" Ball Penetrator PT05194 Hardness Test Block Superficial Rockwell Scale 45T, Approximate Value 10, Material: Brass, For use with 1/16" Ball Penetrator PT05195 Hardness Test Block Rockwell H Scale, Approximate Value 90, Material: Brass, For use with 1/8" Ball Penetrator PT05196 Hardness Test Block Rockwell R Scale, Approximate Value 80, Material: Brass, For use with 1/8" Ball Penetrator PT05197 Hardness Test Block Rockwell H Scale, Approximate Value 120, Material: Brass, For use with 1/2" Ball Penetrator PT05198 Hardness Test Block Superficial Rockwell Scale 30Y, Material: Brass, For use with 1/2" Ball Penetrator PT05199 Hardness Test Block Plastic Rockwell M Scale, Material: Brass, For use with 1/4" Ball Penetrator PT05200 Hardness Test Block Superficial Rockwell Scale 15W, Material: Brass, For use with 1/8" Ball Penetrator PT05245 C Regular with Certification PT05246 Indentron PT05247 Versitron PT05248 N Regular PT05249 1/16" (1.6mm) Ball Unit PT05250 1/8" (1.7mm) Ball Unit PT05251 1/4" (6.4mm) Ball Unit PT05252 1/2" (12.7mm) Ball Unit PT05253 1/16" (1.6mm) Carbide Ball Unit, with Certification PT05254 1/8" (1.7mm) Carbide Ball Unit, with Certification PT05255 1/4" (6.4mm) Carbide Ball Unit, with Certification PT05257 3000kg High Brinell Test Block PT05258 3000kg Low Brinell Test Block PT05259 500kg High Brinell Test Block PT05260 500kg Low Brinell Test Block PT05261 Test Block - Heavy Load, Vickers 5kg Load PT05264 Heavy Load Indentor PT05265 Min. Brinell 2 1/2mm Ball PT05266 Min. Brinell Block 187 1/2kg, 2-1/2mm Ball PT05267 Pedestal Anvil PT05268 2-1/2" Flat Anvil PT05269 Small V Anvil PT05270 Large V Anvil PT05271 8" Anvil Testing Table PT05272 HRC 3-Block Master Calibration Kit PT05273 HR30N 3-Block Master Calibration Kit PT05276 HRB 3-Block Master Calibration Kit PT05278 C&30N Scale 6-Block Master Calibration Kit Contact Starrett Features 1/4" Diameter Ball Hardened Steel Specifications Made in America: Yes Downloads Starrett Hardness Testers (Bulletin 592) Complete product listing and reference data collection of all Starrett Hardness Testers and Accessories. Starrett Hardness Testers (Bulletin 592) Complete product listing and reference data collection of all Starrett Hardness Testers and Accessories. 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. 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