ringer / wringer are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
ringer: (noun) a person who is almost identical to another. (noun) a contestant entered in a competition under false pretenses. (noun) (horseshoes) the successful throw of a horseshoe or quoit so as to encircle a stake or peg.
wringer: (noun) a clothes dryer consisting of two rollers between which the wet clothes are squeezed.
ringer: r·IH·ng·er
wringer: r·IH·ng·er
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)