Dynamic Buffers

Dynamic buffers are tools to modify the inventory that gets exposed to your online sales channels, and also to protect your inventory at certain locations and they always act at the SKU level

Think of them as modifiers for your inventory, so if you have 10 units available of the product with SKU 12345, and you create a buffer of 5 for it, your channel (BigCommerce, Shopify, etc) will only get 5 available instead of 10. 
A buffer can combine channel, location, and SKU to generate a different effect on the final quantity that gets exposed to the channel.

Let's go through some important buffers you can define:
Global Buffer (1)*:
A global buffer applies to all SKUs through all your channels. This affects the total inventory exposed to each channel for each SKU. You create a global buffer by only setting the quantity on the buffer. 
Channel Buffer (2):
A channel buffer applies to all SKUs but only for the specified channel, and it affects the total inventory exposed to each product for the channel. This kind of buffer can be created by setting a channel for your buffer and a quantity, leave the SKU and location untouched. 
Location Buffer (3):
A location buffer modifies only the quantity available for products at the given location. They affect the total quantity exposed to the channels but they also affect the way we allocate orders to your stores if you're using Sqquid's Order Routing, potentially protecting inventory there.
For example, if you have 3 store locations called A, B, and C and you don't want C to be fulfilling or assigned online orders, you may just create a very big buffer for location C, so that when we apply the buffer the inventory for all products at store C becomes 0. 
SKU Buffer (4):
An SKU Buffer is basically a modifier for a single SKU through all your channels. Simply set the SKU you want the buffer to take effect on and a quantity and you're done. 
You may combine the different buffer types just by setting the Channel, Location, and SKU to create very specific buffers. 
For instance, you could create a buffer that protects inventory at a certain store for web orders coming from a specific channel. You can also create buffers that affect the inventory exposed to a specific channel for a specific SKU and no other product or channel will be affected.