GSM eavesdropping devices from the Stone Age
What some providers market today as 'modern GSM surveillance electronics' often has shockingly little to do with professional technology. In truth, it is often primitive DIY work: loose GSM components, a cheap battery, quickly soldered together - functional at best by chance.
Instead of a stable, secure casing, the fragile interior is wrapped with shrink tubing, hastily shrunk with hot air. Cables, antennas, and wires hang unprotected outside, dangle from the device, and are mechanically and electrically a ticking time bomb. Access to the SIM card? Cut out of the shrink tubing with a razor blade - a clear indication of how little thought was given to security, durability, or service.
Such constructions are not only amateurish but highly problematic. Electrically unsafe, mechanically unstable, and in the worst case even dangerous. Whether they function reliably at all is often purely a matter of luck.
These devices do not come from professional development, but from the workshop of hobby electronics enthusiasts whose goal is quick money - at the expense of customers who cannot recognize what is actually being sold to them here.
„Geiz ist geil“ erweist sich in diesem Bereich als besonders gefährlicher Irrtum. Wer auf den billigsten Anbieter setzt, riskiert nicht nur den Totalverlust seines Geldes, sondern auch Schäden, Fehlfunktionen oder Sicherheitsprobleme, die weit über den ursprünglichen Kaufpreis hinausgehen können.
Below we present a collection of such offers where you should exercise extreme caution.
Improvised GSM module in heat shrink tubing 
Loosely soldered components and unprotected battery 
SIM access roughly cut 
SIM access roughly cut 
SIM access roughly cut 
SIM access roughly cut