His tools were the tried-and-true measuring instruments of an older time - callipers, microscopes, magnifying glasses, light-boxes and rulers.
(His tools; were; the tried-and-true measuring instruments of an older time - callipers, microscopes, magnifying glasses, light-boxes and rulers)
His tools
were
the tried-and-true measuring instruments of an older time - callipers, microscopes, magnifying glasses, light-boxes and rulers