OPIOL QUALITY® Sleeve nuts with raised head and slot, M5 x 14, made of stainless steel, A1 VA (10 pieces), nut slotted nut, sleeve nut, slotted drive, spacer sleeves, rustproof : Amazon.de:
BESTOMZ T-nut, M5 thread, slim, 50 pieces (M5 x 10 x 6). : Amazon.de: DIY & Tools