These simple accessories let you use the hardest drill bits with less risk of snapping them.

Milescraft 1385 DrillBlock+ Handheld Metric Drilling Guide, Drilling Jig with Drill Guides for 9 of The Most Common Drill Bit Sizes, Precision Drilling Tool...
5.0

Draper 20229 Drill Guide, 4/5/6/8/10/12mm Drill Block, Angle Drill Guide
4.0