Goa'uld scanning grenade

The scanning grenade is a device used by the Goa'ulds to scan any possible presence on the other side of a Stargate wormhole.

Overview
These silver hand held spherical devices were presumably employed during exploration of new worlds with a Stargate. It is thrown through the Stargate whereupon it lands in its new environment. Once there, part of the device opens on the top and emits an orange scanning beam. Somehow the datas are received on the other side (SG1: "Children of the Gods").

Apophis used this device on Earth to find a host for his queen Amaunet (SG1: "Children of the Gods").

"Children of the Gods" (1997)
As a wormhole has been established on the SGC Stargate, Senior Airman Weterings approches the event horizon. As she near it, a small circular metallic device drops from the wormhole at her feet. It emits noise and an orange beam scans her. When she picks up the device, Serpent guards come out the worhmole and she drops it.

Later, a Serpent guard picks up the scanning grenade before leaving the room.