Please note that the EnerGel Combo refills are different from the standard Tradio line. The EnerGel refills are much shorter and there is a spring at the end of the pen body to accommodate the reduced refill length. However, you can unscrew the body and give it a few good shakes. The spring can be removed and then standard Tradio refills will fit. The pen body that has an obsessive following is now available as a popular gel ink pen. The Pentel Tradio EnerGel Combo takes the look of a regular Tradio body and combines it with an EnerGel refill - thus two product lines are "combined" into one single product. Get the best of both worlds by trying out the brand new Tradio EnerGel Combo Pen from Pentel France! The nature body series has matte finish bodies.