These handles work well around my printer. They hold a 2 mm & 2.5 mm wrench.The handle below the hex portion is hollow. I used a # 44 drill bit for the 2 mm wrench and a #36 drill bit for the 2.5 mm. Just drill the undersized hole to fit the wrench you want to use. I drilled the handle in a lathe for a nice hole on axis. The short leg of the wrench was hit with a grinder, broken off in a machinist vice and flattened on the end. Press fit. Scaling is another option for different sizes.