supply of a6 calibration block , a6 calibration block as per fig.4 of is: 4904/2006, reaffirmed 2023 or latest, with calibration certificate from nabl accredited laboratory along with traceability, for ultrasonic testing of axles and wheel s for evaluating near and far surface resolving power for shear wave and compression wave. the block shall h ave dimensions of 25mm x 50mm x 150mm with weight approximately 1.5kg having six holes of dimaeter 1.5mm each, 10mm apart and at depths of 1mm, 2mm, 3mm, 5mm, 10mm and 15mm respectively. material of the block shall be as p er cl.3 of is: 4904/2006, reaffirmed 2023. (copy of specification & drawing enclosed) the block shall be supplied wi th a warranty of 24 months for manufacturing defects. quantity: 01 no. [ warranty period: 24 months after the date of delivery ] ]