Is this pistol SA only or DA/SA? Is there an external safety and, if so, how does it work? Thanks for your answers.
P365 is a Stryker-fired weapon. Similar in design to a double-action hammered weapon.
glocks perform two actions when you pull the trigger: cock the striker spring, and release it. that technically classifies it as double action.
...on the other hand, springfield XD's are single action: racking the slide "cocks" the striker spring, while pulling the trigger simply releases it and therefore only performs one action.
Most of these types of guns, Sig P365 included, are generally referred to as double action despite the way the function internally. You pull the trigger and get one shot and a complete cycle which readies the next shot. They do not have an external safety.