Universal Hardware PartsChina 2mm 2.5mm 3mm 3.5mm 4mm 4.5mm Grade G100-G1000 Material AISI 1010/1015/Q235 Solid Loose Carbon Steel Balls for Bicycle Bearing Pulley Slingshot Slide Rail Craft, Find details about China Steel Ball, Carbon Steel Ball from 2mm 2.5mm 3mm 3.5mm 4mm 4.5mm Grade G100-G1000 Material AISI 1010/1015/Q235 Solid Loose Carbon Steel Balls for Bicycle Bearing Pulley Slingshot Slide Rail Craft