Lotus Connect Store › Steel Extension Spring - 6" length - 0.25" diameter - Eisco Labs Image 1 of 1 Steel Extension Spring - 6" length - 0.25" diameter - Eisco Labs $1.81 6" Steel extension spring with 0.25" diameter.25" diameter loops on either endClosely wound steelStandard wire gauge 19This 6" long steel extension spring is a great accessory for demonstrating physics concepts related to Hooke's law Quantity: Add To Cart Added! 6" Steel extension spring with 0.25" diameter.25" diameter loops on either endClosely wound steelStandard wire gauge 19This 6" long steel extension spring is a great accessory for demonstrating physics concepts related to Hooke's law