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M5 Specification

Outside Diameter is 25mm
Thread length is 10mm
Inside Diameter is 15mm 
Overall height is 36mm
Marine grade
A4 316 Stainless Steel Polished 

M6 Specification

Outside Diameter is 28mm
Thread length is 12mm
Inside Diameter is 15mm 
Overall height is 38mm
Marine grade
A4 316 Stainless Steel Polished 

M8 specification

Outside Diameter is 34mm
Thread length is 13mm
Inside Diameter is 20mm 
Overall height is 45mm
Marine grade A4 316 Stainless Steel Polished 

M10 specification

Outside Diameter is 43mm
Thread length is 17mm
Inside Diameter is 25mm 
Overall height is 51mm
Marine grade
A4 316 Stainless Steel Polished

M12 specification

Outside Diameter is 51mm
Thread length is 20mm
Inside Diameter is 30mm 
Overall height is 69mm
Marine grade
A4 316 Stainless Steel Polished