The voltage detectors can give a false "no voltage" reading when being used to test live wires for electric current, posing shock, electrocution and burn hazards to consumers.
The "Slider Bracelet" in the jewelry making kit contains high levels of lead. Lead is toxic if ingested by young children and can cause adverse health issues.
The bicycle seatstay or linkage component parts used to connect the seat tube and rear axle dropouts can be incorrectly sized which can cause the frame to collapse, posing a fall hazard to the rider.