1) Product: gas and oven knob 2) Materail: aluminium,plastic,zinc,bakelite 1) As we are factory, we insure first-hand price, cheap and compitive. 2) To make sure high quality and high service from us. Before trail order, we will sent samples to customer for approve. Before shippment, QC full inspection aluminium,plastic,bakelite knob (gas cooker and oven)