> ## 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). # Clock Pendulum Suspension-Spring Information ### Clock Pendulum Suspension-Spring Information [![](https://www.clockworks.com/wp-content/uploads/2020/11/suspension.demo_.wtr_-700x700.jpg =365xauto)](https://www.clockworks.com/product/clock-pendulum-suspension-spring-hanger) ### Click on the picture to shop Clock Suspension Springs on Clockworks.com The following is a discussion on clock pendulum suspension-spring information. Naturally, [suspension springs](https://www.clockworks.com/product/clock-pendulum-suspension-spring-hanger) do not have to be exact in length. If the clock runs slow, simply raise the [pendulum bob](https://www.clockworks.com/product/mechanical-clock-pendulum-bob) with the [rating nut](https://www.clockworks.com/product/clock-pendulum-rating-assembly) at the bottom. Likewise, if the clock is running fast then turn the [rating nut](https://www.clockworks.com/product/clock-pendulum-rating-assembly) to lower the [pendulum bob](https://www.clockworks.com/product/mechanical-clock-pendulum-bob). [![](https://www.clockworks.com/wp-content/uploads/2020/11/wood.stick_.pendulum.rating.nut_.wtr_.jpg =349xauto)](https://www.clockworks.com/product/clock-pendulum-rating-assembly) ### Click on the picture to shop Clock Rating Assembly on Clockworks.com ### Most common springs By and large, [suspension spring A](https://www.clockworks.com/product/mechanical-clock-suspension-spring) is the most common style [suspension spring](https://www.clockworks.com/product/clock-pendulum-suspension-spring-hanger). Of course, it is most likely the one by default. If the old [suspension spring](https://www.clockworks.com/product/clock-pendulum-suspension-spring-hanger) looks similar to this one then it is right. As a general rule of thumb, small mantle clocks take [suspension A1](https://www.clockworks.com/product/mechanical-clock-suspension-spring), wall clocks and small grandmother units will take [suspension A2](https://www.clockworks.com/product/mechanical-clock-suspension-spring). The [A3](https://www.clockworks.com/product/mechanical-clock-suspension-spring) size is for grandfather clock units with a larger [pendulum bob](https://www.clockworks.com/product/mechanical-clock-pendulum-bob) diameter. [![](https://storage.crisp.chat/users/helpdesk/website/-/9/5/9/1/9591a3f915bf7800/suspension-a_52jfpf.jpg)](https://www.clockworks.com/product/clock-pendulum-suspension-springs-assortment) ### Click on the picture to shop Clock Suspension Spring A Assortment on Clockworks.com This size can also be seen on Grandmother clocks with larger bob diameters. Use the larger [A3](https://www.clockworks.com/product/mechanical-clock-suspension-spring) with large bob diameters so the bob will not wobble front to back. If using a pendulum with a [bob](https://www.clockworks.com/product/mechanical-clock-pendulum-bob) of 8 1/2 inch diameter or larger please order [Suspension A3](https://www.clockworks.com/product/mechanical-clock-suspension-spring) for this reason. ### Not as common [Urgos](https://www.clockworks.com/clock-movement/urgos-clock-movement.html) uses the single hook style as seen in picture [suspension B](https://www.clockworks.com/product/urgos-clock-pendulum-suspension). However [suspension A](https://www.clockworks.com/product/mechanical-clock-suspension-spring) was the very most common to use. [![](https://storage.crisp.chat/users/helpdesk/website/-/9/5/9/1/9591a3f915bf7800/suspension-b_52y1wx.jpg =253xauto)](https://www.clockworks.com/product/urgos-clock-pendulum-suspension) ### Click on the picture to shop Clock Suspension Spring B on Clockworks.com Very old antique round movements mainly use [Suspension C](https://www.clockworks.com/product/antique-clock-suspension-spring) and [Suspension D](https://www.clockworks.com/product/antique-pendulum-suspension-spring). These are mainly [French](https://en.wikipedia.org/wiki/French) clocks and US made units made prior to 1945. [![](https://storage.crisp.chat/users/helpdesk/website/-/9/5/9/1/9591a3f915bf7800/suspension-c_1j786pq.jpg =240xauto)](https://www.clockworks.com/product/antique-clock-suspension-spring) ### Click on the picture to shop Clock Suspension Spring C on Clockworks.com [![](https://storage.crisp.chat/users/helpdesk/website/-/9/5/9/1/9591a3f915bf7800/suspension-d_1yv49mj.jpg =248xauto)](https://www.clockworks.com/product/antique-pendulum-suspension-spring) ### Click on the picture to shop Clock Suspension D on Clockworks.com *The content of this website is copyright by [Clockworks Inc.](https://www.facebook.com/ClockworksUSA)