The filter Eureka HEPA Dust Cup Filter DCF14/DCF10 is the correct filter for your Eureka Optima Upright Vacuum model # 437. 
For use on 430 series lightweight uprights. For optimum performance, make sure to change your filter at least every 6 months. Eureka part # 62721B (replace part # 62731 & 62731a); because these part numbers can constantly change make sure to verify the correct filter by the label stating DCF14 or DCF10 or both. 

Here is a link to our website so you can view and purchase the Eureka HEPA Dust Cup Filter DCF14/DCF10:

Eureka DCF10 / DCF14 ZVac HEPA Filters (2 Pack) - Similar to 62396 - by ZVac