Abstract: A connecting clamp for a pneumatic apparatus (e.g. apparatus for operation with compressed air) which apparatus comprises a substantially parallelepiped shaped body (10) of plastic material associated with a bottom (30) and a lid (40) placed on two opposite faces of the body. The clamp is constituted by a rectangular aluminum alloy plate (50) of substantially the same size as one of the other faces of the body, against which it is applied. The clamp includes a central tapped sleeve (58) for making connection to other pneumatic equipment and lugs (57) projecting perpendicularly from the plate, each lug having an orifice (56) with its axis extending in a plane parallel to the plane of the plate and capable of receiving a rod or screw for fixing the clamp to the body, the rod or screw also passing through the lid or the bottom to fix the lid or the bottom to the body.