The Leapers UTG Pro SD Monolithic M-LOK Forearm provides an improved handhold and additional M-LOK real estate for accessories. Compatible with and requires the UTG Pro Monolithic M-LOK handguard for the HK MP and similar clones. FeaturesExtended 4.2" cylindrical forearm compatible with most K-length suppressors and upTwo-inch inner diameter provides the necessary space required for M-LOK hardware to clear most bare or wrapped suppressors and improves heat dissipationCounts as one 922(r) compliant part