# Append Datasets and Merge Blocks allow selection of output type

The **Append Datasets** and **Merge Blocks** filters each have a new advanced property enabling the selection of the output type. If the output type is specified as a "Polygonal Mesh", then only polygonal meshes from the inputs/input blocks are merged into an output of type "Polygonal Mesh". If the output type is "Unstructured Grid", then all inputs/blocks will be merged into an output of type "Unstructured Grid".
