The rPro +17.5mm Mini Prism w/ Plate for Leica Instruments is a more affordable yet equally precise and accurate alternative to the Leica GMP101. Super compact and highly accurate, it’s a great surveying tool for everyday use. Highly accurate results: Measuring only 3.5” wide and 5.25” high, this prism gives extremely accurate results because of its small size. It has a constant of +17.5mm and a built-in bubble level to ensure the correct position before measuring. Built to last: The rPro +17.5mm Mini Prism is made from precisely ground glass, equipped with a durable aluminum target plate lined with highly visible reflective tape. The target plate and prism holder are made of durable aluminum that withstands harsh weather conditions. The package also comes with an attaching spike and a carrying pouch.