Home / Services HK 91 93 G3 33 53 90 / PSG1 MSG90 Forward Assist Button/Plunger Factory HK You cannot add "HK PSG1 MSG90 #30T Locking Piece" to the cart because the product is out of stock. PSG1 MSG90 Forward Assist Button/Plunger Factory HK$16900 SKU: PSG1FA-1 Categories: MP5 & 90 Series, Services - HK PSG-1, Services HK 91 93 G3 33 53 90 Tags: HK21, HK21E, HK23, MSG90, PSG1 Product ID: 5819 PSG1 MSG90 forward assist button/plunger. Also fits 21/23 and other belt fed HKs. Factory HK part New old stock Black Somewhat rare Only a few in stock! Product is out of stock Estimated Re-stock date: November 8, 2021 Notify me when this product is back. Please enter a valid email! Subscribe Description Additional information Description PSG1 MSG90 forward assist button/plunger. Also fits 21/23 and other belt fed HKs. Factory HK part New old stock Black Somewhat rare Only a few in stock! Additional information Weight 1 oz Dimensions 2 × 1 × 1.5 in Manufacturer HK 922r Qualifying Part NO – NA Related products Out of stock HK SG1 Cheek Rest Stock for Single Rear Pin Receivers MP5 33 53 93 $19900 Out of stock HK PSG1 Style Trunnion RCM $9900 Out of stock MP5 4 Position Lower Grip Frame Housing Used $4900 Out of stock Tan Polymer HK Vertical Grip 416A5 G28 MLI RAL8000 $4900