diff --git a/commands/nntp_probe.ts b/commands/nntp_probe.ts
index 74c02f4..def2aec 100644
--- a/commands/nntp_probe.ts
+++ b/commands/nntp_probe.ts
@@ -30,6 +30,14 @@ export default class NntpProbe extends BaseCommand {
   @flags.boolean({ description: 'Only the span itself and the wider ones, no bisection' })
   declare noBisect: boolean
 
+  @flags.boolean({ description: 'Without XFEATURE COMPRESS GZIP' })
+  declare plain: boolean
+
+  @flags.string({
+    description: 'Only spans from the article of these sizes, e.g. "8,16,24,32,48,64"',
+  })
+  declare sizes?: string
+
   private timeoutMs = 20_000
   private info = { count: 0, low: 0, high: 0 }
 
@@ -41,10 +49,14 @@ export default class NntpProbe extends BaseCommand {
     this.info = await client.group(this.group)
     client.close()
     this.logger.info(
-      `${this.group}: ${this.info.count} articles, ${this.info.low}–${this.info.high}.`
+      `${this.group}: ${this.info.count} articles, ${this.info.low}–${this.info.high}${this.plain ? '; plain' : '; compressed'}.`
     )
     const span = (from: number, to: number) =>
       [Math.max(this.info.low, from), Math.min(this.info.high, to)] as const
+    if (this.sizes) {
+      for (const n of this.sizes.split(',').map(Number)) await this.probe(...span(a, a + n - 1))
+      return
+    }
     this.logger.info('The span and wider ones:')
     await this.probe(...span(a, a + size - 1))
     await this.probe(...span(a, a + size * 32 - 1))
@@ -98,7 +110,7 @@ export default class NntpProbe extends BaseCommand {
       user: env.get('NNTP_USER'),
       password: env.get('NNTP_PASSWORD'),
       secure: env.get('NNTP_SECURE', true),
-      compress: true,
+      compress: !this.plain,
       timeoutMs: this.timeoutMs,
     })
   }