Startco Pty. Ltd. is the Queensland distributor for Stemar Electrical Products Pty. Ltd. which began trading in the electrical industry in 1970.

Stemar was the first Australian manufacturer to install sophisticated electronic testing equipment and one of the first to be Quality Assurance accredited by Standards Australia. Stemar manufactures transformers, distribution and control equipment.

Current Transformers are divided into 2 major categories.
Measurement: Intended for use with indicating or integrating meters.
Protection: Intended for use with protection devices

Current transformers can be constructed in a number of different ways.
Wound Primary: with a fixed primary with a number of turns around the core the winding is fully insulated and form an integral part of the assembly.
Bar Primary: this has a fixed insulated primary conductor passing through the core and essentially the primary conductor is equal to 1 turn.
Bushing Type: this has no primary winding; it is for use with a fully insulated conductor acting as the primary winding.
Window Type: this has no primary winding but it normally has insulation in the window so that conductors can be passed through.