Centec 8-inch auto-pneumatic indexing rotary table. The standard model was arranged to index 2, 3, 4, 6 and 12 divisions with alternative plates to manage 2, 4, 8 or 2, 5 and 10 divisions and others available to special order. The unit could carry 100 lbs and was controlled by a hand, foot or cam operated valves and with or without automatic timing. Up to 120 indexes per minute could be performed - the speed of rotation being  inversely  related to the load. Units could be combined in a controlled sequence or integrated into other timed mechanical systems as required for production processes. In "pre-computer" days these devices were widely used not only on all sorts of production processes including the usual milling , drilling and tapping but with applications as diverse as soldering, welding, hardening, rivetting, swaging, letter and number stamping, assembly of stacked components in a precise order, etc.

Centec 16-inch  auto-pneumatic indexing  rotary table. This heavy unit with a load capacity of 600 lbs was able to index any angle divisible by 3 up to 180 degrees (a total of 60) by the simple means of positioning a button in a slot. Alternative plates were available for different requirements. Rotation was normally clockwise but anti-clockwise units were supplied to order.