HEAT RESISTANT BOROSILICATE GLASS - Manufactured from high quality heat resistant borosilicate glass , CHIMNEY MEASUREMENTS – Width at base 6.5cm dia., Height: 24.5cm, Maximum width: 8cm, Width at top 4.5cm , ROBUST & PROTECTIVE PACKAGING - All of our glass oil lamp cowls are boxed in robust protective packaging , WORRY-FREE RETURNS - We offer a no-quibble 100% satisfaction money-back guarantee with all our products , PLEASE NOTE – Dimensions can vary by up to 3mm, due to the manufacturing process ,