BS standards issued by the British Standards Institution cover metric and imperial fastener series used in UK and Commonwealth construction, rail, energy and marine projects.

BS to ISO & GB Equivalents

• BS 4190 ≈ ISO 4016/4034 — ISO metric black hexagon fasteners
• BS 3692 ≈ ISO 4014/4017/4032 — ISO metric precision hexagon fasteners
• BS 1083 — Imperial precision hexagon fasteners
• BS 4395 — High strength structural bolts

Popular BS Standard Numbers

Metric Series

• BS 4190 — ISO metric black hexagon bolts, screws and nuts
• BS 3692 — ISO metric precision hexagon bolts, screws and nuts
• BS 4933 — ISO metric black cup and countersunk head bolts and screws
• BS 6107 — ISO metric precision black fasteners (part 1-8)
• BS 7419 — Hexagon bolts and screws for high strength structural bolting
• BS 7644 — Specification for hardened and tempered high strength bolts and nuts

Imperial Series

• BS 1083 — Precision hexagon bolts, screws and nuts (BSW/BSF threads)
• BS 1768 — Unified precision hexagon bolts, screws and nuts
• BS 1769 — Unified black hexagon bolts, screws and nuts
• BS 916 — Black cup head bolts and nuts
• BS 57 — BSW bolts, screws and nuts (coarse)
• BS 450 — BSF bolts, screws and nuts (fine)

Structural & Special

• BS 3139 — High strength friction grip bolts and nuts
• BS 4395 — High strength friction grip bolts, nuts and washers (grades 8.8/10.9)
• BS 4604 — High strength friction grip bolts for structural engineering
• BS 3410 — Metal washers for general engineering purposes
• BS 4320 — Metal washers for general engineering (metric)