> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://clockworks.crisp.help/sitemap.xml
> Use this file to discover available pages before exploring further.
> Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash).

# What Clock Movement Suspension Spring do I need?

${vimeo}[Suspension A](744267389) 
Most common suspension is our letter A. The suspension spring A is the most common suspension spring needed. If working with a floor clock it would be suspension A2 or A3 depending on the pendulum. For a pendulum with a 6 1/2 inch (165mm) or less bob diameter, use suspension A2. If larger, use suspension A3. Suspension A4 is only for huge clocks with tubes hanging off the back of it (tubular bell units) with a very heavy pendulum.
https://www.clockworks.com/product/clock-pendulum-suspension-springs-assortment