S&W states that magazines for current SD pistols (like this drum) are also compatible with the SDVE40.

ProMag magazines are designed utilizing both traditional stamping and welding of heat-treated high carbon steel, and modern precision injection molding of mil-spec polymer compounds. Every ProMag magazine is backed by a lifetime guarantee against manufacturer's defects. This ProMag S&W SD40 Drum Magazine features the same patented follower system as the ProMag 5.56mm AR-15 drums for ultra-reliable feeding. Over molded heat-treated carbon steel magazine upper housing combined with an impact resistant polymer drum housing and stainless-steel magazine spring for rugged use. Heavily field tested by ProMag's USPSA shooting team, this drum magazine sets a new standard for .40 S&W firepower and reliability.

Specifications and Features:
50-round drum magazine
Smith & Wesson SD40 .40S&W Pistol
Magazine body constructed of heat treated steel with black oxide finish
Injection molded magazine follower
Magazine spring formed from heat treated chrome silicone wire
Polymer
Black
Made in the USA

Fits:
Smith & Wesson SD40 .40S&W Pistol