The ASP D2 Heat (OC) Insert for Metro Defender (ASP part no. 55110) is a replacement insert for ASP D2-size Defenders, the size formerly sold as the Key Defender insert. It carries ASP maximum-strength, law-enforcement-grade OC and is sold singly. Swapping it in is how you reload a used or date-expired Defender without replacing the device.

Key Specifications

• This listing is a single Heat (OC) insert, one refill for one reload.
• The formulation is 10% oleoresin capsicum with 1.4% major capsaicinoids, rated by ASP at two million Scoville Heat Units.
• Heat inserts include invisible UV dye, added for 2024 to help law enforcement identify an assailant.
• Each insert is date-coded so you know when to replace it, and ASP asks that expired inserts be disposed of under local environmental rules.
• The insert is precision machined from aerospace aluminum and solid brass with a specially produced valve system and patented dispensing mechanism.
• It is compatible with Metro D2 and Sport D2 Defenders, and the older Key Defender takes the same insert size.

Frequently Asked Questions

Which Defenders does this insert fit? It is compatible with ASP Metro D2 Defenders and Sport D2 Defenders. ASP says the insert size is unchanged from the original Key Defender.

How strong is the Heat formula? ASP lists it at 10% oleoresin capsicum with 1.4% major capsaicinoids, or two million Scoville Heat Units, and it includes invisible UV dye.

Does the insert expire? Heat inserts are date-coded for reliability. After the date marked on the insert it should be disposed of in accordance with the environmental regulations in your area.

Buy the ASP D2 Heat (OC) Insert for Metro Defender

Keep a spare Heat insert on hand so a used or expired Defender can be reloaded quickly. Order it from our Lubbock, Texas gun shop for fast shipping, and see our other pepper spray and OC products.