FDM stands for Fused deposition modeling.The part/model is built based on a single layer of Plastic that fuses together to create a 3d object.For ex. Layers of plastic are visible to the eye and Model might have imperfections.

SLA is a form of 3d printing that requires UV/Photo-Solidification .Through lighting a resin material it hardens creating a 3d model. Able to get close to a liquid mold injection part creating higher resolution than an FDM part. Not all 3d prints are perfect please view the pictures posted and ask questions.  3d printed parts are put to sale once printed and tested for functionality and inspected for quality.