This document describes SPULLOWS, a software tool for designing, modeling, costing, and preparing quotations for metal expansion joints. SPULLOWS allows users to design bellows elements and associated hardware, generate 2D and 3D models, automatically create bills of materials and cost sheets, and reduce the time required for the entire process from over 6 hours to just 20 minutes. The software guides users through the design process, calculates key bellows parameters, and automatically generates scaled drawings, 3D models, and cost reports.