Do we know if any of the US military equipment that we are shipping to Ukraine is being replaced?

Are they purposefully drawing down our own military of equipment? Anyone know where to look for purchasing?

Given today's latest $500 million drawdown announcement.

MORE UKRAINE AID: The 41st drawdown of equipment for Ukraine is valued at up to $500 million and, according to the Pentagon focused to support Ukraine’s counteroffensive operations, strengthen its air defenses to help Ukraine protect its people, as well as additional armored vehicles, anti-armor systems, critical munitions, and other equipment.

It includes additional munitions for Patriot air defense systems; Stinger anti-aircraft systems; additional ammunition for High Mobility Artillery Rocket Systems (HIMARS); demolitions munitions and systems for obstacle clearing; mine clearing equipment;155mm and 105mm artillery rounds; 30 Bradley Infantry Fighting Vehicles; 25 Stryker Armored Personnel Carriers; Tube-Launched, Optically-Tracked, Wire-Guided (TOW) missiles; Javelin anti-armor systems; AT-4 anti-armor systems; Anti-armor rockets; High-speed Anti-radiation missiles (HARMs); precision aerial munitions; small arms and over 22 million rounds of small arms ammunition and grenades; thermal imagery systems and night vision devices; testing and diagnostic equipment to support vehicle maintenance and repair; spare parts, generators, and other field equipment.