We carry a wide range of gas and heating books, both domestic & non domestic. GID1 is our best selling 'foundation' gas installer manual and continues to be an essential 'on the job' technical reference source for the modern gas professional. USP1 The gas industry unsafe situations procedure is a must-have publication for any gas professional. We have over 20 CORGI technical manuals available. You may also like to view our CORGI Forms & Pads section.