M8-1.25  Stainless Steel Button Head Socket Cap Screws.  These are made from A2 (18-8) Stainless Steel and use a Hex / Allen key to drive.

Available in 10mm - 80mm lengths

Diameter : M8 / 8mm

Thread Size :  1.25 - UNC / Coarse Thread

Length : Available from 10mm - 50mm long.

Drive : M5 / 5mm Hex Key - Available here

Type : Button Head Socket Cap Screw

Matching Nut & Washers: M8 - Available here

System of Measurement : Metric

Material : Stainless Steel Grade A2 / 18-8 / Type 304

Specifications : ISO 7380 / DIN 9427