This 2 in 1 Small Bolus Gun from Stone Mfg can take the guess work out of 'what size bolus gun fits each bolus'. The bolus gun has a spring loaded center shaft. The overall length is 11 1/4". inside diameter is 1/4" and 3/8". Comes with 2 interchangeable heads to fit most boluses.
Fits Copasure 2gm and 4gm boluses. Stone #64200