Machinist Flexbar B Blocks Size 1  Set No. 16093  Complete w/ Clamps & Test Ball VG++ 
This set is in very good condition with instructions and the original box. 

 ENABLES YOU TO INSPECT AND DETECT OUT-OF-ROUND CONDITIONS AND LOBES WITH NO DAMAGE
                                    TO PARTS AND NO DAMAGE TO BLOCKS                                                                  
                                                                                                                         
     SPECIAL FEATURES:                                                                        
• Accuracy of Balls: 25 millionth of an inch sphericity                        • Class 40 cast iron, used on base and housing, is                      and medium set. 50 millionths of an inch on large set.                      • Pair of blocks assembled using metrology.
• Overall accuracy of matched pairs ±5 microns.                               • Spacers are hardened through and precision                              • Balls Rockwell C-62 — Surface finish 0.2 microinches.                      ground by pairs. 
• Calibrated balls are certified.
    SPECIAL FUNCTIONS:
• Balls undergo slight elastic deformation when parts are loaded on. Hence parts will not be damaged while being inspected or produced.
• Detection of lobes and superimposed lobes made easy.
• Easy readjustment of balls which provide new bearing points.
• Handles diameters up to 15 inches.
• Increased contact area due to special geometric spacing of balls in blocks.
• 8 contact points per pair of blocks share load distribution.
• Balls are self-aligning and hard wearing.
• 1 each precision spacer per block provides 2 different angles per pair.
• Simply turn each block 90° and inspect component using both angles.
• Special inspection set ups using cylinder squares now possible.                                                                                                   

 Any questions please ask.