This is an SSD adapter designed to fit into the 3.5" drive bay on (some) Dell PCs. It fits into the existing caddy as a push fit and is offset.
The caddy requires the drive to be off-centre whereas other adapters I found were centred, which fouled the connectors.
I have kept the body as slim as possible to minimise material. The item will flex but this is stopped by the insertion of the SSD.
Should be OK in any material, I think. I chose ABS but PLA should be fine too.
Screw in the SSD and away you go
Simply screw the SSD into the appropriate mountings and then flex the adapter into the caddy using the captive lugs.