Coil stamp

Coil stamps are those sold in strips, typically from vending machines.
 * Coil stamps often have two parallel imperf sides. This makes them less likely to jam vending machines.
 * Syncopated perfs are also used.
 * Some coils are perfed as the regular issue making them hard to tell apart. In certain cases they are different perf gauges. Sometimes, a clean machine-made trim on two sides, which might mean trimming off perfs, identifies coils.