This invention relates to a gas tank handling attachment for a truck mounted forklift truck (TMFL) comprising a frame, a pair of clamping arms pivotably mounted on the frame, and a pair of pivoting rams mounted on the frame, operable to pivot the clamping arms to and from a stowed configuration and an operating configuration. The frame comprises a pair of spaced apart uprights bridged by a bracing cross-member, and there is provided, mounted on the frame, means to releasably engage a fork carriage. One of the clamping arms is mounted on one upright and the other clamping arm is mounted on the other upright. In the stowed configuration, the clamping arms are substantially parallel to and extend upwardly from the uprights, and in the operating configuration the clamping arms are substantially orthogonal to and project forwardly from the uprights. An operator can operate the attachment to engage/disengage a gas tank from inside the driver's station of the TMFL.