This is a type of ammunition encountered Saturday and Sunday we weren’t familiar with here. It’s not a rubber bullet, but rather a sponge grenade, made to be fired from a 40mm launcher. Penny & ruler in second pic for scale, it’s 40mm (1.6 inches) wide & ~65mm (2.6 inches) long 
This is an example of injury from Raleigh, on an individual’s upper arm. Their entire bicep felt bruised and was difficult to move for 5 days
Before presenting our research, we feel there's an important point to emphasize. None of the weapons used in these protests are non-lethal. Based on one study 3% of people hit by less lethal rounds died [1]. This type of ammunition is no exception. Sources will follow thread.
When studying riot control devices, it's often useful to look at previous struggles which have faced these measures. Rubber bullets were developed for British colonists in Northern Ireland, tear gas for the British empire's repression in Cyprus.
It appears sponge grenades were first used in Palestine by Israel, at least since 2009 [2]. Sponge grenades were developed in a, blue-tip format, with a plastic base and foam rubber impact tip. In 2015 they developed a harder rubber black-tip version [3], which we've seen
The blue-tipped rounds are likely manufactured by Safariland [2], while the closest picture we've found to the ones encountered here is Nobel Sport Spartan LE-40 [4].
We do not believe use of sponge grenades should be allowed period. Currently use of sponge grenades is not approved for distances closer than 10 meters, or aimed above the chest, based on US military guidelines and industry recommendations [5]
In Raleigh we saw multiple sponge grenades fired from closer than 10 meters. We didn't document any head injuries, but the person whose upper arm was hit is tall enough that the impact was around average head height.
Sponge grenades claim to reduce injury from rubber bullets, but according to a 2019 study, "the injuries it causes characterized as wider and more comminuted" [6]. Comminuted refers to a bone fracturing into more than 2 fragments. Eye injuries were most common, then jaw/tooth.
Palestinian Dr. Nasser al-Jaberi, the Director of the Emergency Room Department at the West Bank’s Arab Society Hospital: "If shot at a very close distance, either sponge round can cause fractures to the skull, which could lead to death" [3]
"Sixteen-year-old Muhammad Abdelmajid Sunukrut was shot in the head from around 30 feet away with a sponge round in August 2014. After struggling for a week in the hospital Sunukrut succumbed to his wounds" [3]. Rest in power.
"In July 2016, 10-year-old Muhyee al-Din Tabakhi was hit in the chest with a sponge round, causing internal bleeding that led to the child’s death" [3]. Rest in power.
Already there have been multiple injuries in the US from sponge grenades in the past week. In Denver, a protester moving to bring medic supplies to other protesters was hit in the face with a sponge grenade, causing a severe laceration and likely fracture [7].
There are other new types of sponge grenades which have soft foam and can transport marking dye, tear gas, or pepper spray. We haven't encountered any of those in Raleigh yet.
Now to the most important part of this thread: how to stay safe. Again we turn to those who have faced this struggle previous. In this comrade's thread, 'sponge baton' is a synonym for 'sponge grenade'
We have been unable to determine if safety glasses will protect eyes, but our suspicion is if they are Z-87+ rated or above, they should be able to at least provide some protection. Z-87+ is rated for a 1/4 inch steel ball fired at 150 feet per second.
As said in the cited thread, the best way to protect your face is to turn, bow, & protect your head/neck with your arms. Running should be avoided if possible- combined with the disorienting effects of gas and less-lethal rounds, it can lead to injuring yourself or others.
We recommend reading this entire thread, as we don't know what weapons we'll encounter in the future. It seems quite likely the Raleigh Pig Department will try to get their hands on whatever they can to hurt us.
