Topographic monitoring requires accessories such as bolts, prisms, and targets. Reference bolts are threaded to accept optical targets. Rotary targets can be also mounted on a simple threaded bar or attached to an inexpensive “L” shaped bracket. The GMP104 equivalent to the Leica mini-prism provides good survey performace. Its aluminum bracket can be mounted and adjusted easily for 3D surveys. Topographic benchmarks and bolts can be supplied when topografic levelling is required.