Do not put the drill hole cutter through the red positioning plate directly as it is only used to draw the installation position of the hinge hole to locate the center hole. After drawing, remove the positioning plate and start drilling. The cutter fit in the plastic template hole) hinge drill is made of premium carbide with the characteristic of high hardness, non-desuitable formation and anti- corrosion. And the hinge drill guide made of ABS plastic, , and portable. 35mm suitable forstner drill bit adopts a center-positioned tip design to make cutting . The drill bit with a detachable depth limiting baffle and a clear scale makes drilling easier and more efficient. Tip: The drill chuck should clamp the hole saw, so that the jig bit will not drift. Hole diameter of red position plate: 35mm/1.4inch. The hinge drill guide can help you draw the perfect hidden hinge hole quickly. And the "V"-locator that works off of a center reference line and quickly locates drill center points so that the hole will not shift. Make cabinet door installation easy and accurate. The concealed hinge kit is working efficiently suitable for timber, plywood, veneer work, great suitable for cabinet, hinge, furniture and mounting plates or other DIY projects. Great suitable for beginners, you can find the center of the hinge and mounting plate quickly. Material: Plastic + Alloy colour: As shown Package Contents: 1 set x 35mm suitable forstner bit(3 Pcs) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.