This is a deck spacer to put in-between your house and ledger board to stop water going from the ledger board into your house framing. (same kind of thing you can buy at the home depot for about $3-$5 each) I suggest a 90% fill to avoid problems while printing. (100% fill was a bit hit and miss to do but is possible) I printed mine directly on my heated plate with no raft but you must have your plate very level to pull that off so level it before you begin. Please be aware I'm not a structural engineer and these may not be strong enough for all i know so print and use these at your own risk. Only print them out of ABS as PLA may biodegrade outside.