This thumbscrew is made in collaboration with Project Airsoft. It replaces the original screw on your pistol’s TDC cover and is fully compatible with: Novritsch TDC cover for SSX23 and SSX303 Hadron Design’s TDC cover for MK23 Most other TDC covers with M4-size threads It’s manufactured with a slightly oversized M4 thread so it wouldn’t turn by itself when installed. It also comes with a dab of pre-applied thread glue to provide even more friction. The screw is made out of anodized 6061 aluminum and has a laser-etched indicator for hop-up adjustment direction. Thumbscrew has knurled sides so you can easily adjust hopup even with gloves. It’s super low profile so it doesn’t get in the way of fiber sights or prevent you from using a holster. It’s a perfect upgrade / fix for SSX303 – no more scratching on the inside surface of the extrusion and no more flexing due it it being much shorter which means you can easily apply more force when adjusting without worrying about destroying the TDC housing. ⚠ During the initial installation the screw can be a bit tight – we recommend screwing it in and out a few times to make it easier to turn.
