Straight line conveyor sortation systems are most cost-effective where the number of sortation points required is relatively small, for instance, 10-40 delivery points.

A number of different types of diverts can be used on straight line sorters with selection based on a number of factors including product characteristics and the required throughput. The range of in-line sorters include devices to sort from 5-20 cases per minute, up to high speed units operating at greater than 200 cartons per minute.

Sliding shoe-type sorters, where the product is supported on tubes or slats, and a positive divert is performed to either side of the sorter by shoes which slide across the tubes or slats, are suitable for throughput rates of between 9,000 and 12,000 items per hour.
As well as providing quiet and reliable operation, sliding shoe sorters can also handle a wide product range from packages as small as 150 mm long and weighing as little as 50 grams up to packages over 1 m long and weighing up to 50 kg.

Tracking is by variable window, but goods cannot be recirculated within the sorter unless conveyors are linked specifically for this reason.

A second straight line sorting option is the steerable roller. Located within the conveyor bed frame, the steerable roller divert is a pop-up mechanism, with the rollers lifting and twisting left or right to gently drive products off the sorter. Throughput rates of around 7500 items per hour are possible, as is variable window tracking.