Us old guys figured this out decades ago, but there are several sizes where metric and inch tools can be interchangable.
For example, 8mm, 11mm, 13mm, 14mm, 16mm, 17mm, 19mm and more, have close matches in inch measurements. And other sizes are also close. The smallest sizes can be useful with Allen wrenches.
And occasionally, when a wrench seems to be a loose fit on a particular fastener, you’ll have the option of a slightly tighter fit by choosing a different tool.
Here’s a chart I did in Excel that shows the exact dimensions of each, and highlights in green some common substitutions.
.
For example, 8mm, 11mm, 13mm, 14mm, 16mm, 17mm, 19mm and more, have close matches in inch measurements. And other sizes are also close. The smallest sizes can be useful with Allen wrenches.
And occasionally, when a wrench seems to be a loose fit on a particular fastener, you’ll have the option of a slightly tighter fit by choosing a different tool.
Here’s a chart I did in Excel that shows the exact dimensions of each, and highlights in green some common substitutions.
.
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