For example, a pencil detonator designed to fire 24 hours after being activated could in reality give a 30-hour delay - if the weather was very cold. Similarly, during hot weather pencil detonators designed to fire after a 12-hour delay could in reality trigger detonation within 10 hours. The main virtue of pencil detonators is their small size and light weight, plus the fact that they are very quick and easy to use.
A pencil detonator designed to explode 24 hours after activation might actually delay up to 30 hours if stored in cold weather, whereas a detonator set for a 12-hour delay could activate within just 10 hours during hot conditions. The primary benefit of pencil detonators is their compact size and ease of use.