To add onto what Oliver wrote, unless you are able to see one of the D-tect sensors in operation, it is difficult to explain or demonstrate in 90-second video. The closest analogy I can think of is a SONAR fish finder used by fishermen on a boat. The display will show a graphic return of something at a distance, except instead of water of varying temperatures, the medium is concrete, drywall, or any of the pre-programmed settings in the sensor, and the distances are in millimeters, not feet.
I've been using my D-tect 150 for over 11 years and trust it when the sensor detects rebar, water pipe, or electrical cables. Prior to using it, my success rate with missing rebar was about 75-percent. Now that I use it for every project that requires drilling into the wall or ceiling slabs, my success rate is 100-percent. If I find rebar, but it is beyond the depth that I want to drill, I can drill in confidence that I will not hit it.
When I drilled the mounting holes for my clamp rack and tool boards, I scanned the wall vertically and horizontally to identify the location of the rebar grid in the areas I wanted to put anchors. This allowed me to adjust my drilling location as needed and put enough bolts into the wall to handle the shear load.
At one of the facilities I supported before I retired, the maintenance personnel were drilling into a concrete wall to mount eight large screen displays for a video wall. No one on the team bothered to scan the wall before drilling the dozens of holes for the brackets. The facility manager had considering buying a D-tect 150, but hadn't been able to justify the expense, so they were relying on luck with every hole. On the third monitor bracket, the technician hit an undocumented high-pressure water pipe that immediately started flooding the mission floor.
The pipe later turned out to be part of the abandoned fire suppression system that had been capped somewhere in the wall instead of being removed. The sudden flow of water also triggered the fire alarm system, which caused everyone in the building to evacuate. The resulting drama resembled a U-boat that had been hit while they scrambled around trying to find any valve that would shut off the high-pressure water. The cost to repair the wall, and replace the damaged furniture, flooring, and equipment was over €30K, which was significantly less than the cost of the D-tect 150. The facility manager now had the justification to buy a D-tect 150 for each team.