A scaffolding tube clamp comprising: a pair of body portions secured together at 90 degrees to one another, each pair of body portions comprising a base and a top, each base and top having a first end hingedly connected to one another to permit the base and top to be rotatably received about an exterior surface of a scaffolding tube, a rotatable bolt engageable with a first hole positioned in a second end of the top and engageable with a second hole in a second end of the base, when the bolt is engaged with the first and second holes rotation of the bolt in a first direction connects the second ends of the top and base and moves the second ends closer to one another in a clamping arrangement about a scaffolding tube receivable therebetween, and rotation of the bolt in a second opposite direction releases the connection between the second ends of the top and the base permitting their rotational movement about the hinged connection, the bolt having a head and a shaft, the shaft having a first threaded portion with a first thread located adjacent to the head, the shaft having a second threaded portion with a second thread at a lower end of the bolt, the scaffolding clamp being characterized by the first threaded portion having a larger diameter than the second threaded portion, the first threaded portion having a coarser thread than the second threaded portion, the first hole having threads complimentary to the first thread and the second hole having threads complimentary to the second thread, the first and second threads having different pitches, and wherein the top includes a tab on an interior surface adjacent to its hinged connection to the base, the tab being engageable to a scaffolding tube received between the top and the base, wherein insertion of the scaffolding tube between the top and the base causes an engagement of the tab with the scaffolding tube and causes the second end of the top to be rotated toward the second end of the base. a pair of body portions secured together at 90 degrees to one another, each pair of body portions comprising a base and a top, each base and top having a first end hingedly connected to one another to permit the base and top to be rotatably received about an exterior surface of a scaffolding tube, a rotatable bolt engageable with a first hole positioned in a second end of the top and engageable with a second hole in a second end of the base, when the bolt is engaged with the first and second holes rotation of the bolt in a first direction connects the second ends of the top and base and moves the second ends closer to one another in a clamping arrangement about a scaffolding tube receivable therebetween, and rotation of the bolt in a second opposite direction releases the connection between the second ends of the top and the base permitting their rotational movement about the hinged connection, the bolt having a head and a shaft, the shaft having a first threaded portion with a first thread located adjacent to the head, the shaft having a second threaded portion with a second thread at a lower end of the bolt, the scaffolding clamp being characterized by the first threaded portion having a larger diameter than the second threaded portion, the first threaded portion having a coarser thread than the second threaded portion, the first hole having threads complimentary to the first thread and the second hole having threads complimentary to the second thread, the first and second threads having different pitches, and wherein the top includes a tab on an interior surface adjacent to its hinged connection to the base, the tab being engageable to a scaffolding tube received between the top and the base, wherein insertion of the scaffolding tube between the top and the base causes an engagement of the tab with the scaffolding tube and causes the second end of the top to be rotated toward the second end of the base.