Type D
Direct Answer
Type D is the old British 5A standard (BS 546, 1934) -- three large round pins in a triangle. It predates and is completely incompatible with the UK's later Type G, and remains the primary domestic standard in India, Nepal, and Sri Lanka today.
Source: BS 546
Specs
| Pins | 3 round pins in a triangle (large, non-coplanar sizing) |
| Rated Current | 5 A |
| Rated Voltage | 250 V |
| Grounded | Yes |
| Common Regions | India, Nepal, Bhutan, Sri Lanka, Namibia, and roughly 40 countries with British-influenced history |
Superseded at Home, Standard Abroad
BS 546 was published in April 1934, replacing an even earlier British standard (BS 317), and remained the UK's grounded domestic plug until the fused BS 1363 (Type G) was introduced from 1947 onward. The two standards are mechanically and electrically incompatible -- a Type D plug simply does not fit a Type G socket, or vice versa.
In the UK itself, BS 546 today survives only in niche applications like stage lighting and switched-lamp circuits, having been fully superseded domestically by Type G decades ago. But in India and several neighboring South Asian countries, BS 546 (as Type D) remained -- and still is -- the primary domestic standard, alongside India's own current-upgraded 6A revision under IS 1293.