Used in England (for general, mayoral and pcc elections) and has a winner takes all approach where voters elect a local MP with one ballot. Typically leads to a two party system
Advantages
+ Delivers a strong and stable government, 2019: 365 seats (56%)
+ Provides a clear winner and is easy to understand, 2019: declared within 24 hours
+ MPs can have closer links to constituency
+ Limits extremist parties
Disadvantages
Results in safe seats and uncompetitive elections. North Shropshire for 200 years, around 250 seats haven't changed in 70 years
Leads to two party system
You can win without 50%, 2017: 43% but 56% of seats
Not representative for smaller parties, UKIP got 4 million votes but only 1 MP in 2015