From Halopedia, the Halo wiki
The Razor's Edge is a named variant of the Z-130 DEAW, modified to fire metastable energy shards similar in operation to the Subanese crystals found in weapons like the needler. Its chassis is based on the regular Z-130's except that the main weapon color is now dark gray with orange and turquoise stripes painted around the weapon's main body and grip area.
The Razor's Edge's first use was towards the end of the Forerunner-Flood war, where the Forerunners faced their extinction from the Flood and became desperate, eventually resorting to experimenting with volatile derivations of hard light. These experiments eventually led to the inception of weapons like the Razor's Edge.
Halo 5: Guardians
The Razor's Edge, a Rare Level 3 REQ that grants 100 REQ Points when sold, operates exactly identically to a normal Suppressor albeit with the added supercombine functionality of the Needler (six shards result in a supercombine) along with the ability to directly damage heavy armor. However, out of all the supercombine-capable weapons in the game, the Razor's Edge has the tightest supercombine time window, lasting only 0.9 seconds. In addition, the Razor's Edge has a lower rate of fire in comparison to the lesser Suppressor models, with only a maximum of 1 round / 0.7 seconds (420 RPM). Despite these drawbacks, the Razor's Edge is the most powerful of the Suppressors, as it has a very high round count (maximum 288) and can deal decent damage to vehicles and heavy armor, even serving as an alternative to the Talon of the Lost if the player is running short on their supply of the latter weapon. The Razor's Edge has an increaesd overall range from the normal Suppressor, with 42.05 m (137.96 ft) in hipfire and 58.88 m (193.18 ft) with Smart-Link.
Unlike the other supercombine-capable weapons in the game, the Razor's Edge's supercombine explosions also disintegrate any dead bodies within their blast radius.
Changes from the Z-130 Directed Energy Automatic Weapon
Halo 5: Guardians REQ cards