Spuhr MP-5 Top Rail C-THRU Black. Height: 25.9 mm/1.02in (from top of receiver to top of rail) Length: 92.0 mm/3.62in (overall) 84.6 mm/3.33in (Picatinny) Weight: 124 g/4.4 oz Specifications for Spuhr MP-5 Top Rail C-THRU: Manufacturer: Spuhr Color: Black Gun Rail: Picatinny Gun Type: Submachine Gun (SMG) Gun Make: Heckler & Koch Gun Model: Heckler & Koch MP5 Length: 3.62 in Height: 1.02 in Weight: 4.4 oz Package Contents: Spuhr MP-5 Top Rail C-THRU Spuhr R-305: MP-5 Top Rail C-THRU Black