This listing is for a pair (2) of improved, super strong replacement dust covers used on the swing arms of current generation (2019 & newer) Permobil Corpus M1, M3, & M5 power wheelchairs and the 2020 & newer F3 & F5. It is shown here snapped into the chassis of a 2020 M3. These only work in the latest generation, not older models. I included a picture of the style of plug these will replace, please confirm the plug/cap you’re trying to replace looks the same. If it looks different, this item will NOT fit your chair. Please note, this is a 3D printed part and is not the exact same profile as the original, but it fits just as well and is MUCH more durable. Each cover is printed in a very durable, somewhat flexible, hard rubber, called TPU. The nature of this material creates a tight seal, negating the need for a rubber O-ring that comes on OEM covers. If you break one, send me a picture and I will send you a new one free of charge. Part dimensions: 1.7 in. x 2.3 in. Sold in pairs (2 pieces total). Usually ships in 24 hours or less.