Booster for on a dining chair . Straps back and underneath are there to fix to your chair but one of the harness straps have gone missing . I have ( see on picture ) a black set of reins which have a harness which might be able to be adapted to use with the seat .
The seat could be used for an older toddler as an alternative to balancing on a cushion but would need adult supervision if used without the harness to ensure child didn’t climb out or slip down .
Collection from Ecclesall S11 off Knowle Lane - (Happy to leave this outside under cover for collection)

Toddler dining booster seat (Ecclesall S11)