Replacement plastic slat locks that fit metal loft bed (bars below mattress).

Bed frames are sold under different names depending on where you bought it. I have seen them from walmart, amazon, and wayfair.

Link to specific bed
https://www.walmart.com/ip/Amolife-Twin-Size-Heavy-Duty-Metal-Loft-Bed-with-Removable-Ladder-Full-Length-Guardrail-Apple-Green/124278641?wmlspartner=wlpa&selectedSellerId=101072144&sourceid=dsn_ad_82a1172e-9aef-4deb-a6c1-b1278a1d5253&veh=dsn&wmlspartner=dsn_ad_82a1172e-9aef-4deb-a6c1-b1278a1d5253&cn=FY25-MP-PMAX2_cnv_dps_dsn_dis_ad_mp_s_n&gclsrc=aw.ds&wl9=pla&wl11=online&gad_source=1&gclid=EAIaIQobChMIg6bBuqKWigMVrAatBh1bVQPVEAQYAiABEgKyqvD_BwE