T-Bolt, Compound Rest, M8 

T-Bolt for compound rest, M8. Length 22mm (0.866") when measured like a bolt. Overall length 27.50 mm (1.08").

The head is 16mm x 15mm x 5.5mm (0.63" x 0.59" x 0.22")

Some machine manufacturers will identify this bolt as GB/T 37. The Guobiao Standards (China) lists GB/T 37 as a bolt for t-slot.

See Used On tab for reference to machines using this part and the corresponding drawing number.