This large insulated discharge wand measures 18. 5" in length. The sphere is made of stainless steel, not cheap aluminium like others on the market. The handle contains a 4mm female port that will accept a 4mm male banana plug connection. Lethan Corporation (Sci-Supply parent company) produces some of the highest quality Van De Graff generators on the market. This large discharge wand is designed for the LC2910 model, but is compatible with most generators with an output of up to 750KV. Quality materials, affordable pricing.