Features: High Quality Material: The drill locator is made of external wrapped plastic material and internal hard metal material which is high density anti-wear and corrosion resistant and can be used for a long time. Self-drilling Guide Hole: The drill locator has a steel drill sleeve embedded in the internal drilling hole to prevent the guide hole from being worn out while drilling which will lead to a larger guide hole and loss of accuracy. Multi-size Drilling: Two drilling aids with different accuracy are available for your choice each positioner has six different size drilling holes they are compatible with most tension screws. Wide Range of Applications: The multi-functional woodworking drilling aid can be applied to cable railing furniture making and DIY woodworking projects use aluminum and stainless steel deck post installation etc. Customer Service: If you confront any problems about our products please feel free to contact us we are ready to help. We will solve your problems as soon as possible. Specification: Material: Plastic Package Size: 140*50*30mm Weight: About 148g Notes: 1. Due to different monitors and lighting effects the actual color may be slightly different from the image. 2. Due to manual measurement please allow 1-3cm deviation. includes: 1Self Centering Drill Jig "