Dụng cụ đo độ giãn bu lông (Stretch Gauge)

Because the commercially available tools for this job (meassuring bolt stretch while torquing bolts during assembly of an engine) are quite expensive and we already had a micrometer gauge at hand - i decided to go ahead and just print myself the rest of the tool needed to get the job done.

The diameter for inserting the tool and the opposing pin are spaced according to the tool i had.
The holes perpendicular to them are for inserting small grubscrews holding the actual tools in place.

The picture in the images section is an earlier prototype of the tool.
The uploaded version is a little more polished.