The planwheels by Scalex – use the Scalex Planwheel sa2 or the Scalex Planwheel XLU2 for use with blueprints, architectural plans, engineering plans or any set of plans or drawings where distances need to be calculated. The difference between the Scalex Planwheel SA2 and Scalex Planwheel XLU2, is the Scalex XLU2 is able to download data to any windows program using the Scalex Scale-Link USB2 kit (sold separate) using a computers USB port. The Scalex Planwheel XLU2 is also bundled with the Scalex Scale-Link USB2 kit at a discounted price. The Plan wheel XLU2 and SA2 has 111 built in scales and the ability to program additional user defined scales. With the XLU2 you can key in up to 19,998 user settable scales. The Scalex XLU2 and SA2 planwheels includes architectural scales, engineering scales, metric scales and mapping scales. The Planwheel XLU2 and SA2 are excellent for quoting and is used in building, construction, landscaping, gardening, electrical work or any field where you need a fast accurate tool for estimating the cost of a job. Need a tool to quickly quote and estimate for building and construction then look at the XLU2 or CA2 Scalex Planwheel.