I purchased a deployant for mine, mostly for the counter-weight. I opted for the WG version. Friendly reminder, while you can use the original strap that you have with the deployant, for it to fit correctly you will need a 125 x 65mm strap. The 5905's strap set up is 22mm at the lugs and 16mm at the buckle. They do not make a strap with these specs so it is a custom order from HSWA. Mien took over 8 months to arrive. Again, not necessary, just wanted to provide some insight.