Description:  6-22mm Woodworking Square Hole Drill Bit Mortising Chisel Tenon Drill Bit.     Specification:  Product Name: Wood Working Square Hole Drill Bit.  Size:  1/4(6.4mm), 5/16(8mm), 3/8(9.5mm), 7/16(11mm), 1/2(12.7mm), 9/16(14mm), 5/8(16mm), 3/4(19mm), 7/8(22mm), 6mm, 10mm, 12mm, 12.5mm, 18mm.  A - (6mm+8mm+9.5mm+12.7mm).  B - (6mm+8mm+9.5mm+12.7mm+14mm).  C - (6.4mm+9.5mm).  D - (6.4mm+9.5mm+14mm).  E - (6.4mm+9.5mm+14mm+16mm).  Material: Bearing steel.  Application:  Suitable for density board, medium density fiber board, particleboard, wood and other wood products.  Suitable for square hole drilling machine, square tenon machine.  Quantity:  Size 6.4-18mm: 1 Pc x Wood Working Square Hole Drill Bit.  Size A-E: 1 Set x Wood Working Square Hole Drill Bit.     Features:  1. Square hole drill can not be used on an electric drill, drill square holes need to fit a square hole drill drilling (mortise and tenon machine) to use.  2. Mortise and tenon square hole drilled by the terrible + outer sleeve in the middle of the combination.  3. Reduce labor intensity of construction workers, speed up the construction speed, reduce construction costs for construction, installation, renovation, decoration industries.  4. Suitable for density board, medium density fiber board, particleboard, wood and other wood products.  5. The utility model in the hole drilled by the rotary body, while the impact of the use of hammer impact force transmitted to the outer body, the material crushing round hole and square head wall, a one-time processing of a square hole, and the dust can be broken slag discharged from the tube.  6. Using different specifications of the square hole drill, matching the appropriate power of the square hole machine, you can play a square hole to meet the requirements.     Note:  If you have no square hole machine,  1, You can use electric drill to drill the hole with the drill bit of the combination.  2, Use the square outer sleeve to beat the hole, and you will get a square hole.     Package Included:  Size 6.4/8/9.5/11/12.7/14/16/19/22/6/10/12/12.5/18mm: 1 Pc x Wood Working Square Hole Drill Bit.  Size A/B/C/D/E: 1 Set x Wood Working Square Hole Drill Bit