The Stanley Intellisensor pro stud detector, locates the edges of wood or metal studs water pipes or joists through drywall and other common wall materials at a maximum depth of 38mm. It has a visual indicator on the screen and an audible tone to indicate stud and joist edges, and it has automatic calibration so no fiddling with dials trying to set it up correctly it also has automatic shut-off for longer battery life, this detector is like new in the original packaging and instructions it even has a new battery fitted so it is ready for use. It cost me £80 so a real bargain at £30 and if it saves you drilling through just one waterpipe or electric cable it will have already paid for itself. phone 07717 477477 07717 4774...(click to reveal full phone number) located near Bury.